Title: The Fourth Deathly Hallow

Author: Gingertart

Team: Snitch

Genre(s): Fandom Crossovers and Literary and/or Historical

Prompt(s): Code of Honour

Rating: PG

Word Count: approx 56,500

Summary: From the private journal of John. H. Watson MD; not intended for publication. Being an account of the strange case of the Fourth Deathly Hallow; in which Dr John H. Watson and Mr Sherlock Holmes save a life, discover the true secret of Professor Moriarty, unravel a time loop or two, encounter a femme fatale, imbibe potions, break into and out of a wizarding mansion, hide in a male brothel, go shopping, track down a magical artefact, almost attend a ritual sacrifice, fail to be Obliviated and totally ignore the International Statute of Wizarding Secrecy of 1692, all in the company of a lank-haired, irascible but secretly besotted schoolmaster, a bemused aristocrat and an increasingly perceptive and enamoured young hero.

A/N: Should I have warned for a distinct lack of overt sex? If you've come looking for pr0n – sorry. The plot-bunny grew to the size of Tyrannosaurus Rex on steroids and kind of took over. / The Harry Potter world and characters are the sole property of J.K. Rowling, Scholastic, Bloomsbury, and Raincoast Books, and Warner Bros., Inc. I make no money from writing fanfiction. / Thank you to my plot-bunny wranglers, Lesyeuxverts, Leela Cat and Klynie, and my betas, Klynie and WhiteCotton.

The Fourth Deathly Hallow

Part 1: A Rumpus in Baker Street

It was in the winter of 1895 that my friend, Mr Sherlock Holmes, was called away to assist Inspector Lestrade of Scotland Yard with a tricky, but essentially commonplace problem involving the loss by fire of a collection of erotic etchings (see the 'The Penitent Artist' in my as-yet unpublished works). I was recovering from a touch of bronchitis brought on by exposure to the capital’s foggy night air, in pursuit of the owner of the etchings. Holmes insisted that I remained in our quarters, with lemon, honey and a medicinal dose of whiskey. This regimen was so efficacious that after two days, a gleam of watery sunshine tempted me outside in pursuit of fresh air and exercise.

During my return home along Baker Street I became aware of an extraordinary rumpus. The traffic came to a halt; drays, barrows, cabs and carriages backing up towards Marylebone with all the shouting and cursing one could imagine. I increased my pace, idle curiosity urging me on, until I saw the crowd gathering around a knot of figures in the middle of the road and I realised that my professional services were required.

Two youths, one fair-haired and one dark, glowered at one another across an older man who sprawled upon the cobbles in an insensible state. I pushed my way to their side.

"What the bloody hell have you done now, you idiot?" demanded the fellow with the black hair and spectacles. His companion, a slender lad wearing what appeared to be an academic or monastic robe, clutched a length of wood in one hand, around twice the length and width of a pencil. Even as I knelt to examine the comatose man, I noted that the youngster brandished the twig as if it was a dagger.

"What have I done? What did you do, Potter?"

"Nothing!" snapped the other, "I told you, I came to collect Snape’s body. I don’t know what you thought you were going to do to him –"

"Bury him! Treat him with the respect he deserves!"

They paused for a moment as I looked down at my unanticipated patient. He was a gaunt man of perhaps forty years of age, with an ill-used and unkempt appearance. His outer clothing consisted of a black robe, similar to that worn by the blond youth. I wondered if they belonged to an obscure monastic order, but all such reflection fled my mind as I turned his head and saw the great gash in the side of his neck, and the blood soaking his shoulder and sleeve.

"Not going to work something Dark on his corpse?"

"Oh for Merlin's sake, he was my Head of house! Just take us back, will you?"

"You take us back, Malfoy! I don't even know where we are!"

Like two dogs squaring up to fight but thinking the better of it, they broke eye contact and the fair-haired lad, Malfoy, noticed me for the first time. His stick twitched in my direction. Despite its flimsy appearance, I flinched. Maybe it was the intensity in his glare, or the fact that he acted as if he held a loaded revolver, not a twig that I could snap with one hand, but I instinctively felt that I was in great peril. Potter reached across and pushed at his wrist, turning the point away from my face.

"It may be more a question of when the hell we are," Potter muttered, staring around.

"Leave him alone," Malfoy said to me. His tone was imperious, his accent cultured and precise.

"It isn't as if anyone can do anything else to him now, is it? He's dead."

"Oy! 'Ow long're you lot going to be blocking the bleedin' road, then? Some of us 'ere've got a living to make, you know!"

All three of us looked up at the burly costermonger who stood over us, hands on hips and chin jutting fiercely.

"Take his feet, we'd better move him to the side," Potter said and Malfoy bristled.

"A simple levi –"

"Just do it, all right? We're attracting too much attention as it is!"

I removed my hand from the poor fellow's neck, where my fingers had been pressed against the flutter of his jugular. It was clear that someone with a level head needed to take control of this outrageous situation.

"Handle him gently; we will need to fetch a stretcher."

"Don't be an idiot," Malfoy said. He did not look at me as he spoke, in the manner of one accustomed to addressing servants, and I suspected that he was neither a considerate nor popular master. Potter, however, turned in my direction, and his intense green eyes narrowed, then widened again behind his round spectacles.

"What?" he breathed as if he did not quite dare to believe my words.

"He's barely alive," I said. Malfoy whirled on Potter with his teeth bared.

"You said he was dead!" he snarled. The stick trembled visibly in his hand. "You lying bastard –"

"He was!" Potter responded in kind, "I watched him die on the floor of the Shack!"

"He was still alive and you left him there –"

"Gentlemen, enough!" I stood up and wiped my fingers on my handkerchief. "He won't be alive for much longer if you keep this up. I say, my good man, if you would loan us your horse-blanket, we can improvise a stretcher and carry this poor fellow out of the road."

A cabby with a black moustache and the lad from the butcher's shop assisted us to carry the lax body to the pavement so that the traffic could get moving again. The onlookers, cheated of their entertainment, soon began to disperse.

"I'm sorry about all that," young Potter said to me. He ran his fingers back through the untidy mop of his hair. "This is all – well, just a mess. I don't know exactly what happened."

"How did you get here?" I asked. "Did you arrive in a hansom?" Potter and Malfoy exchanged a glance. My first assumption, that they had been knocked down while crossing the road, had been supplanted by the thought that the man had been injured falling from a moving carriage. Now it was clear that he had been hurt even before he arrived in Baker Street. I bent over him. "This looks like a bite," I whispered and neither youth replied, which only confirmed my suspicion. "What was it? A dog would have ripped out his trachea; even a giant cat would have crushed the throat rather than tear the flesh in this way."

"It's a long story."

"We need to get him to a healer," Malfoy said tersely.

"I apologise, I failed to introduce myself. Dr John H. Watson at your service. "

"I'm Harry Potter, that's Draco Malfoy and this is Professor Severus Snape."

"Professor? I assumed that he was a priest or monk."

Malfoy gave a faint snort of derision.

"I'll take him to Saint Mungo's, Potter."

Potter frowned, shaking his head.

"Dr – Watson? Where are we and what's the date?"

Their lunacy must have been contagious for I found myself responding to Potter's question.

"Baker Street, London, and it is Wednesday the 11th of December, 1895."

"Oh shit," Potter whispered, "I was afraid of that."

"Saint Mungo's is still –"

"We don't know if there is a Saint Mungo's here, or even a Hogwarts. Let's get Snape somewhere safe and then discuss our options."

It pained Malfoy to go along with this suggestion, but he gave a very reluctant nod.

"I live further along the street," I said, "You are welcome to bring him to our rooms until a better alternative presents itself." I confess that I was greatly intrigued by these two eccentric young men and their sick professor. Little did I realise then that my invitation was to precipitate the most bizarre adventure in Sherlock Holmes' long and illustrious career.

While I cleaned, stitched and dressed the wound in Professor Snape's neck, his young companions continued to squabble.

"I'm going to Saint Mungo's first, I'll bring back a Healer if I can, or at the very least, some healing potions."

"How are you going to pay?" Potter enquired, pitching his voice low. It was clear that Malfoy, at least, did not care what I overheard.

"Galleons, Potter, what did you expect, fairy gold?"

"And how much legal tender have you got?"

"What're you talking about? I've five galleons here –"

"If it's minted in the twen – in our century, you'll be arrested for trying to pass counterfeited money." He lowered his voice further. I may have been mistaken, but I thought that I caught the word 'goblins'.

There was silence for a minute.

"I'll be back shortly. Don't go anywhere."

"Malfoy! Don't be a berk – oh shit."

Malfoy strode out of the room. A moment afterwards, the house reverberated to a report as sharp as a gunshot. I leaped up but Potter held out a hand in a placating gesture.

"I'm sorry, he's an idiot. He hasn't done any damage, honestly. Oh, this is such a mess." He shook his head. "You said your name's Dr Watson; you don't live with a friend, do you?"

"Of course," I said, returning to my patient and my bandages. "You may have heard of him; Mr Sherlock Holmes."

"The famous detective?" Potter said in an oddly hollow tone, as if he was on the verge of laughter or tears.

"I assure you, if you've done no wrong, you've no reason to fear Holmes."

"Dr Watson, you won't believe what I'm afraid of," Potter said, his voice shaking.

"You would be surprised what Holmes and I have seen and done." I sat back, satisfied that Snape's wound was as neatly stitched and dressed as any war wound I ever tended in Afghanistan, and turned my attention to the man's clothing. "Lend me a hand, Mr Potter; we need to get him out of these blood-soaked garments."

I saw Potter's Adam's apple bob as he swallowed, but he nodded and came to my side. Gently we stripped the man and dressed him in one of my night-shirts to preserve his modesty, leaving him upon the sofa wrapped in a blanket. He was pale and chilly; clearly he had lost so much blood that his life hung by a thread. I said as much to Potter as I stoked the fire.

"I hope Malfoy gets back soon," he said, more to himself than to me. I handed the clothing to Mrs Hudson, who clucked over the poor gentleman and promised to see what could be done to salvage his garments, and then brought us a pot of tea and plates of ham sandwiches. As Potter and I made a desultory meal, I was able to examine him covertly. He wore ill-fitting trousers of coarse blue fabric and a short-sleeved singlet, brightly coloured, of a textile that I could not identify. His loose jacket was also of a style and material that was unfamiliar to me, and I had never seen anything quite like his shoes.

"Tell me," I asked, as I offered him the mustard pot, "what is the purpose of the stick that you carry?" I indicated the slender length of wood, tucked in the waistband of his trousers. His hand paused momentarily as he dropped a dollop of mustard on his ham. Then he gave me an odd, quirky little smile.

"It's a wand." He said no more, but I sensed that he was waiting for me to respond and I obliged.

"Your friend handles his as if it was a weapon."

"He isn't any friend of mine," Potter said immediately. "We were enemies at school, but I suppose we're reluctant allies until we get ourselves out of the awful mess we've fallen in."

"I assume that the Professor was at the same institution?"

He nodded and sipped his tea.

"Yeah, he taught us."

"To use your – wand?"

"Not exactly, he was always against foolish wand-waving – his wand! Oh no!" He leaped to his feet. "Where are his robes? His wand must be – oh!"

I held up the length of wood, which I had removed from the pockets of the bloody clothing, along with a handkerchief and a surprisingly heavy leather pouch. Potter sank back into his seat with an expression of profound relief. "Oh, okay, thanks. May I have them?"

It was with some reluctance that I handed over the articles; I had hoped to examine them and perhaps find out a little more about my visitors. Potter carefully opened the pouch and then he glanced at me out of the corner of his eye. It was the look that someone might cast when they were about to do something that they felt would merit disapproval. I turned away and busied myself with pouring another cup of tea, careful to ensure that I did not obscure his reflection in the polished silver sugar bowl: Holmes had taught me well. Potter drew out his wand, tapped it upon the pouch and whispered something under his breath.

It was all I could do to restrain my shock. In the distorting mirror of the silverware, the pouch appeared to expand, unfolding to the size of a lady's reticule in an instant. He peered inside, then removed a handful of tiny glass phials and began sorting through them in feverish haste. Before I could object, he rushed to his unconscious schoolmaster and carefully dripped the contents of one of the phials between his lips.

"Just wait a minute!" I strode to his side, not a little alarmed. "What do you think you are doing, young man?"

"He has a first-aid kit," Potter said, carefully pulling the cork from another phial. "He's got a healing draught here."

"There is no such thing!"

I reached to grasp the little glass jar but he evaded my hand.

"I'm afraid there is," he said, with surprising gentleness, "and this is a blood-replenishing potion, thank God."

I was about to protest more strenuously when there was a powerful crack from outside the door and Malfoy rushed in. His pale hair was mussed and he appeared wild-eyed and frightened.

"Potter, we're in bigger trouble – what're you doing?"

"He had a first-aid kit in his robe with healing draught and blood replenisher."

Rather than object, Malfoy nodded and said, "Careful he doesn't choke. Here, I'll hold his head up." Together, they drizzled a thick and unpleasant-smelling liquid into Snape's mouth, and then Malfoy stroked his throat, as well as he could for the bandages.

"Gentlemen," I said, "you will kindly cease this behaviour at once. There is little anyone can do for this man, he's dying and those foul-smelling brews will do nothing but hasten his end."

"That's where you're wrong." Malfoy spoke with an off-hand disdain that set my teeth on edge, and Potter glared at him.

"Shut up, Malfoy! Dr Watson, I'm sorry –"

"Stop apologising, he's a Muggle."

"He's helping us!"

"There isn't anything any Muggle can do to help us! Besides, we're in deep shit, there's a war going on here."

"What?" At these outlandish words, the blood seemed to drain from Potter's face. "Where have you been?"

Malfoy lowered his voice, but in a careless way that suggested his contempt for me was still quite profound.

"Saint Mungo's, or rather, the empty site where I thought it to be, then Malfoy Manor, where the elves tried to set the dogs on me. The Leaky Cauldron is where it always was but there were only a few squibs who scuttled away like frightened mice and refused to speak to me. The wall at the back showed spell-damage and Diagon Alley is locked down tighter than a house-elf's arse; I couldn't get in."

Potter was trying to hush him, glancing my way. Malfoy sneered. "We'll Obliviate him before we leave. How's Professor Snape doing?"

They both leaned over the helpless schoolmaster. I glanced his way and bit back a gasp. The face that had been deathly pale was still sallow, but there was a faint colour in the lips and cheeks and his black eyelashes fluttered even as I approached. He no longer looked like a man at death's door, but one who was merely sick and exhausted.

"He needs to rest," Potter muttered. "We shouldn't move him yet, even if we knew where to go."

"He'll know," Malfoy said with satisfaction and settled down to doze in my armchair.

I sat at the table with a notebook and pencil, writing down everything I had seen and heard, in a manner that I hoped would reveal to Holmes that my powers of observation are acute and my brain alert, if even if they can never achieve the standard set by the master.

As soon as I heard Holmes' step on the stair, I hurried out to intercept him and directed him up to my bedroom, where he sat upon the bed and listened to my account of our visitors. I expected him to ask if I had raided his store of morphine or cocaine. He did eye me somewhat askance, and I doubt that my distracted manner reassured him. He snatched up my notebook and perused it before handing it back.

"Well, well, how very curious. Do you know that some of your words waken a feeling of unease in me, which is profoundly disturbing?" He stroked his chin. "Did you note the colour of any soil upon the soles of their boots?"

"No, I confess that I did not."

"A pity; I should have liked to know which direction they came from, since you insist that they had not arrived by carriage. Was this 'wand' that you speak of sharpened to a point or did the tip appear to be sticky? Dear me, Watson, your understandable concern for your patient has rendered you remiss in your duties as my assistant! Never mind; all can be redeemed even at this late stage. Let us go down and you may introduce me to our mysterious guests."

"Holmes." I placed a hand upon his sleeve and he paused, gazing curiously at me. "Holmes, there is something uncanny about those two young men. I do not entirely trust them."

Holmes rubbed his palms together, as eager as a famished man sitting down to a laden table.

"My dear Watson, we have encountered many a rogue in our years together."

"I don't think that they are felons. This is something else."

"I shall take note of your concerns, old friend. Your instincts are generally good even if your powers of observation are sometimes a little lacking. Come along."

He led the way down the stairs, but as he approached the doorway to our sitting room, he halted, staring down at the floor.

"What is it?" I went to his side. I could see nothing but two tiny splinters and a little mud that may have fallen from the kindling when the maid came in to light the fires.

"Curious," he murmured, then flung open the door and I followed him into the room.

Malfoy lounged in an armchair, idly twirling his wand between his fingers, while Potter sat beside the patient upon the sofa.

"This is my friend, Mr Sherlock Holmes," I said. Potter immediately got to his feet and held out a hand.

"Harry Potter, sir. Pleased to meet you." His companion stood up tardily and muttered "Draco Malfoy." Such evidence of ill manners did not sit well with his aristocratic air.

"How may we aid you, gentlemen?" Holmes enquired. Malfoy simply stared at him in a slightly vacant fashion, but Potter, after a sharp glance at him, which did not go unnoticed by either of us, stepped forward.

"We're already very grateful to Dr Watson for his help and we'll be out of your way as soon as Professor Snape's well enough to be moved."

"He hasn't yet regained consciousness; I cannot permit you to leave."

"Of course not," Holmes agreed with alacrity. "Watson, I believe that Mrs Hudson's spare room is still empty since her sister's visit. I'm sure that she would be willing to rent it to your new friends for the short time necessary."

"I shall enquire at once."

"That would be great," Potter said and Malfoy unbent enough to give a quick nod. Holmes went to help himself from the teapot keeping warm beside the fire.

Part 2: The Watcher in the Garden

Mrs Hudson was happy to grant the use of her empty room and I left her lighting the fire and making up beds for the injured man and his companions.

I paused at the top of the stairs. A tall window looked out upon the paved yard below, where our maid was on her way in with a bucket of coal. Next door's cook stood on the other side of the fence, her breath cloudy on the still, chilly air as she tossed scraps into the chicken coop. The two spoke briefly, while beyond them, a dark figure watched from the shadow of the washhouse. I was puzzled, for surely the servants should have noticed the stranger in Mrs Hudson's back garden. It seemed not, and as they returned to their duties, the watcher looked up at the house and I instinctively drew back behind the curtain. I saw only a pale face and a long black garment, like a woman's overcoat, and a white hand that tucked a slender piece of wood into a sleeve.

Holmes had settled himself at the dining table with the newspaper when I returned.

"Does anyone know why this house should be under surveillance?" I enquired, bringing out my pipe and tobacco pouch. Holmes grunted and put down the paper.

"I have two suggestions; one being that scoundrel Howells is up to his old tricks and the other, that whoever caused Professor Snape such inconvenience is still upon his trail."

Potter shook his head emphatically.

"That's impossible, he's dead."

"Ah. Then the fact that our observer also carries a wand is mere coincidence?" I asked.

Grey eyes and green met across the room.

Potter snapped, "You were followed back here!"

"That isn't possible –"

"With a tracking charm, it damn well is!"

"Who, then?"

"How the hell should I know? You were the one who said there's a war going on!"

"It has the same feeling as – you know."

Holmes sat with his sharp face jutting forwards, like a leashed hound, quivering with eager anticipation.

The two antagonists noted his interest; Malfoy displayed his customary disdain but Potter flushed.

"You'll be delighted to see the back of us, I'll bet," Potter said, "You must think we're mad."

"You appear sane enough to me," Holmes remarked. "Watson, is that a furtive step upon the stair?"

We both recognised the faint creak of the loose floorboard on the landing. With no more than a nod, Holmes snatched up the poker and we took up positions one on either side of the door. A second later, it burst open to admit a figure in whirling black robes who pointed a wand at the two young men and exclaimed "Petrificus Totalus!"

Potter and Malfoy, caught in the act of drawing their wands, froze as if turned to stone, only their wildly rolling eyes betraying their alarm. The intruder began to turn towards Holmes as my friend brought the poker down with a satisfying crack on the wrist that held the wand. The slim spill of wood spun across the floor but our success was short-lived. With a cry of "Accio wand!" and a triumphant snarl, our assailant was once again armed, this time with the other hand, and facing my friend.

"I've had enough of your damned interference, Sherlock Holmes! Avada – "

The expression of dawning horror in Potter's eyes was enough to pull me from my shock. I raised my hand and shot the man in the back with my old service revolver.

"I shot him at point-blank range," I said, placing my gun upon the sideboard. "Where the blazes did he go?"

"He Apparated."

The scratchy rasp of a voice was unfamiliar. I turned to find myself appraised by a pair of shrewd dark eyes. Pale and shaky, Professor Snape had nevertheless raised himself up on one elbow upon the sofa. I hurried to his side.

"My dear sir, pray lie down! You are in no condition to move anywhere." He allowed me to prop him against a pillow. Holmes meanwhile had approached the two young men, who were lying like toppled statues in the positions in which they had been caught by the eerie enchantment.

"Not dead, yet trapped like flies in amber. What were the words? 'Petrificus Totalus'?"

"Please," whispered Snape, "a wand?"

I went to Potter and with a murmured apology, extracted the Professor's wand from the young man's trouser pocket. I returned to the sofa. Snape had eyes for nothing but the length of wood in my hand; he snatched it from my grasp and the next moment, the tip was pointing at my forehead. It wavered slightly as Holmes spoke.

"Professor Snape, a loaded revolver is aimed at your head. If you harm Watson, I shall fire it without compunction. Let us see if you can fend off a lead bullet with that wand of yours."

What a bizarre tableau we must have formed. Snape's trembling became more evident until he dropped his hand, sighed and then turned the wand upon Potter and Malfoy. "Finite Incantatem." The words were barely audible, but their effect profound. The two young men scrambled to their feet.

"Snape!" cried Potter, while Malfoy exclaimed "Professor!" and both flung themselves to their knees beside the sofa.

"Thank Merlin you're alive," Malfoy said.

"Yeah, I can't believe it. I was so sure you were dead; if for one moment I'd realised that you were still alive, I'd have asked Hermione to use her dittany and done everything we could to help you. We won, you know! Thanks to you, he's gone."

"Although the gods only know what Potter has done now, since we seem to have been thrown back in time?"

"Oy, I didn't do anything! You were the one who made a grab for Snape's – Professor Snape's body, I just tried to stop you –"

"Oh yes, using which spell, Potter?"

"Shut up, you were casting one yourself –"

Snape held up one hand and into the ensuing silence, he gasped

"Where is the pocket watch?"

Potter looked blank and Malfoy frowned.

"Was it a pocket watch? You were holding something small and metallic in one hand, I thought Potter was going for it and that's why I tried to stop him."

"Dr Watson gave me your wand, first aid kit and handkerchief." Potter looked at me and I shook my head.

"There was no watch."

"It must still be in the shack, Professor, where you dropped it."

Snape closed his eyes.

"Where are we?"

"London, 1895, in the rooms of a certain Dr Watson and Mr Sherlock Holmes."

Snape's eyes flew open again and he mouthed the word "What?"

"I know," Potter said, placing a hand for a moment on his shoulder. Snape glared until he removed it. Malfoy merely looked puzzled.

"Is that a Muggle thing?"

"What is a 'Muggle'?" I asked. Malfoy sniffed and looked away.

"I infer that we are 'Muggles', Watson." Holmes thrust his hands into his pockets, although I noted the bulge of my revolver in his jacket. Holmes was taking no chances. "I've long thought that I caught hints of another world underlying the one we know, underneath even that murky layer of cutthroats and thieves that lies beneath the innocent face of our city. Now I have proof and I find myself exhilarated, vindicated and yet never more concerned." He looked down at the professor. "Tell me, is it possible to erase or alter a memory in a human mind?"

"It's a spell called 'Obliviate'," Potter said. Holmes turned to him.

"I pride myself upon the fastidious arrangement of my own memories, that I keep the little attic of my brain in precise order. Now a man, whom I believed to be dead, walks and breathes and is able to manipulate the very stuff of reality. Can you explain this?"

"I can try, although you'd get a better explanation from Professor Snape."

"As Professor Snape's physician, I cannot allow it until he has rested."

Snape raised a languid hand in protest but he could barely keep his eyes open.

"Come," I said, "Mrs Hudson has made you up a bed and she is preparing some beef broth for your supper. Gentlemen, we will need to assist the professor up the stairs."

As we helped the sick man to his feet, I noted that Malfoy slid his wand into his hand and whispered under his breath. Between them, Potter and Malfoy lifted him as if he weighed no more than thistledown and conveyed him to his bed. Mrs Hudson soon arrived with a cup of broth, which Snape swallowed with some difficulty, then he curled up beneath the eiderdown and soon fell into a deep sleep. I followed the young men down to my sitting room, where Holmes awaited us with every sign of impatience.

"Oh yes, I recognised him," said Holmes, holding a lighted taper to his pipe, "even though I believed him to be dead by my own hand."

"It was Moriarty, then?" I whispered and he nodded. Potter sat forward in his seat.

"Well he's a powerful wizard; he used a wandless 'Accio' to call his own wand. What do you know about him?"

"He is a terrifying criminal," I said, "and a master of subterfuge and obfuscation."

"So he's in both the wizarding and Muggle worlds," Malfoy mused. "You said that he died?"

"I watched him tumble over the Reichenbach Fall near Meiringen in Switzerland. He struck the rocks and was swept downstream."

"So he might have Apparated away from the river, or else he tampered with your memory of the event."

"Whatever the case may be, he convinced me of his death," said Holmes. "Hah! There is a brief span of time following his apparent death, during which I can recall nothing. Now I understand that even as I faked my demise, he was busy simulating his own. Having spent years completely hidden beneath my notice, why should he suddenly reveal himself, unless because of your sudden appearance?" He cocked an inquisitive eyebrow at our young guests. "What do you know of him?"

"The name rings a bell," Malfoy muttered. "History of magic, Potter?"

"Don't ask me, I slept through most of Binns' classes. I've heard Moriarty's name, but only associated with Mr Holmes." Potter blushed and stared down at his feet in their curious shoes.

"Is it not time you told us the truth?" Holmes' voice was quiet but there was steel beneath its gentlemanly tones. Malfoy scowled and Potter flushed an even brighter pink.

"Look, we haven't lied to you."

"You have been, shall we say, sparing with the truth? You are risking not only your own lives, and that of the sick man upstairs, but those of myself and Watson and anyone else unfortunate enough to become embroiled in this affair." Holmes sprang up and paced across the hearthrug. He pointed at Malfoy with the mouthpiece of his pipe. "You, young man, regard folk with lesser abilities than your own – 'Muggles' I believe? – to be wholly inferior. I hope that Watson and I have disabused you of this notion to some degree, since you would now be dead or captured had Watson not shot Moriarty as he attempted to kill us."

Malfoy looked uncomfortable at this assessment, although he rallied swiftly.

"I doubt if any Muggle weapon could so much as touch a wizard."

"He was shot," Holmes stated. "There are spots of his blood on the carpet near the doorway, and I caught him a crack across the wrist with the poker that must have inconvenienced him for a while, but we must be alert, surely he'll come back. If he has only a flesh wound and if he has access to cures such as those you used on your professor, he may return very soon."

"We can sort that." Potter got to his feet, with a look of adamant determination that made me wonder if he had already faced more hardships and setbacks in his short life than many. "Malfoy, I can set wards but I've never had to protect anything as large as this house before. Do you know anything about warding a large building?"

Malfoy narrowed his eyes for a moment then stood up.

"I've helped my parents to update the wards on the Manor."

"Camouflaged wards as well? We want to attract as little attention as we can."

"Yes, Potter, camouflaged wards. Let's get it over with."

Both young men drew their wands and strode out of the door. Holmes and I exchanged looks of mingled concern and exasperation.

"Dear me, Holmes," I said, "Maybe those two should be given boxing gloves and put in a ring together to sort themselves out."

Holmes shook his head.

"I suspect that they have already fought too many times for that to put an end to their rivalry. Let us hope that facing a common enemy allows them to achieve a truce, if not friendship."

"I wouldn't have thought of it," Potter said as they came back into the room, pink-cheeked from the cold. "Turning a Muggle-repelling charm inside out and attaching it to the wards so it allows Muggles in and out but hides us from wizards! Did you invent it yourself, Malfoy?"

"Slytherins do occasionally invent things that aren't entirely Dark."

He sounded grumpy, as if resenting the compliment, or perhaps his own reaction to it.

Potter shrugged and went to warm his hands at the fire.

"What have you done?" I asked. Malfoy looked as wary as ever but Potter seemed to be an open-hearted young man, for all his evident experience of peril, and he replied willingly.

"We've made it so that Muggles – non-magical people, that is – can come and go as usual, but anyone with magical abilities will find it hard to enter the house, and we'll know if they try." He took out his wand and twitched it, and a faint, musical chime sounded in the room, as if someone had gently tapped the edge of a bell with a fingernail. "If you hear that, it means someone apart from Snape, Malfoy or me has tried to enter carrying a magical object and has been repelled."

"Moriarty was able to do 'magic' when his wand was on the floor," Holmes pointed out. "Could he get in without it?"

"A wizard or witch without a wand is either very careless or very desperate; even a very powerful wizard like Moriarty. Any magical objects in his possession would trigger the wards."

"So," Holmes took up his pipe to resume his interrupted smoke, "you were going to tell us what really happened to you. You have travelled a long way, have you not? I find myself wondering how long you took on your journey."

"One hundred and three years, seven months and a couple of days."

Even Holmes appeared shaken, although his recovery was swifter than mine.

"This 'magic' of yours was able to carry you across time?"

"And space."

"From Scotland, I judge?"

"What? Well, yes –"

"From a war zone, in your world, to another in ours? What did your history books have to say about this nineteenth century war? Surely your wizard's world has records of its own?"

"You'd heard of me and Holmes," I said and Potter appeared embarrassed.

"In the world I came from, your names were famous in the Muggle world. Snape and I had both heard of you because –"

"Snape doesn't have anything to do with the Muggle world," Malfoy muttered and Potter let out a sharp breath.

"Of course he does, you twit."

Malfoy went red in the face, as if he had been mortally insulted.

"He's a great wizard, not some Mudblood trash –"

"Malfoy," said Potter, and his voice was quiet, steady and clear, yet something thrummed in the room, a vibration just below the level of hearing, "Snape is a half-blood, his father was a Muggle."

Malfoy's hands clenched and unclenched at his sides.

"You're lying."

"Why should I? My mother was Muggle-born, my best female friend is Muggle-born and I'm not ashamed of either, they were very clever witches. Snape and Tom Riddle were both half-blood."

"Tom who?" Yet there was something about Malfoy's eyes that suggested that he knew the name, and that he was trying to deny knowledge of something that hurt him deeply.

"Tom Riddle, Lord Voldemort."

Malfoy flinched visibly.

"Don't."

"He's dead."

"No," Malfoy whispered, "he isn't born yet." He crossed his arms over his chest and clutched at his shoulders, as if icy cold. "Dear gods, we could find his parents. We could stop it all."

"Malfoy! Draco, no. We can't just wade in and try to change time, or at least, not without knowing what the hell's going on first."

Malfoy sat down in the chair nearest the fireplace, hugging himself. Potter sighed and looked at Holmes. "You were both famous – will be famous, but not as real people. You see, in our world, you were both characters in stories written by a man named Arthur Conan Doyle. My aunt used to like detective films; she watched all the Sherlock Holmes classics."

"Mortdelavie was a wizard," Malfoy said in a monotone, "he was the Dark Lord of the last decades of the nineteenth century. Binns taught us about him. He took over the Muggle criminal underworld and the wizarding world and almost destroyed wizarding culture in the process."

"Why do we know nothing of this?" I demanded.

"International Statute of Wizarding Secrecy, 1692," Malfoy said bleakly, while Potter snorted.

"Would you have believed us if we'd just turned up and told you?"

"Look," Malfoy said, "I'm going to bed. I'm tired, I've got a splitting headache and we need to have this discussion when Professor Snape's awake otherwise we'll just end up repeating ourselves."

The truth of this was undeniable; we all had a great deal to think about.

Passing by Mrs Hudson's spare room on my way to bed, I saw that the door was slightly open and I wondered if I should check upon my patient.

"How are you feeling, Professor?" Malfoy's voice was quiet, filled with concern.

"Cold."

I glanced in, and saw Malfoy raise his wand, twisting it as he whispered an incantation. "There, that should last a few hours. Wake me if you need the charm renewing. God, these Muggles live in primitive conditions, don't they? It's so icy in here."

Snape ran his fingers across the dressings on his neck.

"What is troubling you, Draco?"

"Potter said that you're a half-blood."

Snape's pale hand paused, then continued its exploration of the bandages.

"Yes."

"And so was the Dark Lord."

There was a longer pause.

"If he says so. Where is Potter?"

"Gone to the bathroom. Do you need anything else?"

"Dreamless sleep."

"We only have your first-aid kit and we already gave you the healing potion and the blood replenishing potion. I'll see what I can get for you tomorrow. Is the venom affecting you?"

"Bezoar."

"You need one? I can try to find –"

"I took one." Snape coughed painfully on the words and Malfoy winced.

"I didn't mean to force you to talk. Wake me if you need me, Professor." He carefully pulled the counterpane up around Snape's chin and I continued on my way.

Part 3: A Wizard Goes Shopping

By the time I had risen, Mrs Hudson had brought up a tray with a dish of bread softened in warm milk. Snape pulled a sour face but began spooning up the gruel.

"You must allow your throat to heal internally," I explained. "Your oesophagus was damaged."

"Tea and toast would be preferable." His voice sounded a little less hoarse today.

"I'll try to get some eggs for you," Mrs Hudson said as she waved in the girl with a bucket of coal. "Coddled eggs would be gentle on your poor throat, and steamed fish with the bones removed. Do be careful, Lizzie, be sure to sweep up the dust when you've finished with the fire. The rest of you gentlemen have kippers for breakfast today."

I thanked her, checked the dressings on Snape's neck and followed our landlady down to the sitting room, where Holmes awaited us.

"Now," said Mrs Hudson, placing the coffee pot on the table, "some business matters need attending to, I'm afraid. If I'm to go shopping today to feed all your extra mouths, I'll need the rent for your room."

Potter looked at Malfoy, who frowned, dug into his pocket and held out a coin. Mrs Hudson took it with a puzzled air.

"But this is foreign."

"Yes," Potter said hurriedly, "it's solid gold. Please take it to a jeweller –"

"No," Holmes interrupted, pulling out his wallet. "Keep your money for now, Mr Malfoy. Take this, Mrs Hudson, and we'll settle up among ourselves." He waited until the good lady had returned to her below-stairs abode before turning to Malfoy. "We have already attracted too much attention; at least let us try to avoid notice from the police. You are likely to be accused of passing counterfeit money. What is that coin?"

"A galleon; wizarding currency."

"Do you have nothing that would arouse less suspicion?"

Potter shook his head.

"I didn't expect to need money and I've nothing to sell. What about you?"

Draco Malfoy folded his arms.

"Nothing I'm prepared to part with, Potter, apart from the money. That'll have to do."

"Oh for – Malfoy! I'll pay you back when we get back home, okay? With interest! I'm not going to let Snape die – again – just because you're too tight-fisted to pay for food and potions and a bed for him." His scowl faded. "Can we transfigure the galleons into sovereigns or something?"

"No, the goblins charm wizarding currency to protect it from replication or transfiguration, otherwise everyone would turn their knuts into galleons, wouldn't they? Didn't you learn anything at school?"

"Very funny; you know damn well how much they don't teach us about wizarding culture at Hogwarts. What do you suggest we do, then? Or do Malfoys expect other people to settle all their debts?"

With an air of great dignity, Malfoy reached into his pocket and took out a gold signet ring with a carved green stone.

"This was my great-grandfather's, my father gave it to me on my last birthday. I hope that you appreciate this, Potter."

"It's for Snape," Potter responded quietly.

"I shall take you to a reputable jeweller," I said, "As I mean to visit the chemist today."

"I need to buy potions ingredients," Malfoy said to Potter. "I can brew a healing potion and blood replenishing draught."

"Give me a list," Potter said at once, "I'll go with Dr Watson."

"Oh yes? And you expect me to stay here, do you, and let you wander off –"

Holmes looked up from helping himself to a kipper and spoke with cool restraint.

"Gentlemen, or should I say, boys, can you not put aside this schoolyard rivalry even for a single hour? One of you needs to remain to protect the household from occult attack by Moriarty and his henchmen and I must admit that despite his outlandish clothes, Mr Potter's manner is less inclined to attract attention than is yours, Mr Malfoy."

Malfoy flushed but did not reply, while Potter very nearly succeeded in suppressing a grin. We sat down to breakfast in a silence that was polite, if not exactly companionable.

"A herbalist would do to start with," Potter said, pocketing the coins from the sale of Malfoy's ring.

"Might I first suggest the second-hand and pawn shops, where you can buy rather less conspicuous clothing for yourself and your friends?"

Potter agreed, so we spent an hour in perusal of tweed jackets, greatcoats and scarves, before sending an errand boy home with a bundle of clothing and we set off for the chemist's shop. My business was soon concluded and my purchases of bandages and liniments directed to Baker Street.

The first herbalist's shop we encountered was unpromising; a quack's emporium of old-wives' cures. Potter sniffed at a jar of some dried vegetation and shook his head.

"Finest saxifrage!" the shop-keeper exclaimed in a spray of spittle. My companion gave a shudder.

"Yeah, right. If I used that, my Professor would skin me alive. It's full of dust and looks as if it's been here for the last five years. Come on, Doctor, we won't find anything useful here."

"I believe that I have passed a herbalist on my way to the library," I mused, "although I have never been inside. It's a poky little shop, hardly big enough to supply many of your needs."

"Let's give it a go."

The shop was indeed tiny, but clean and well-organised. Potter brought out his list and began reeling off his requirements.

"Madder, ribwort, elecampane, carnelian – no, chamomile... um, porcupine... hang on...."

A tiny old woman came out from behind the counter and grasped his elbow, peering up into his face.

"What did you say, dear?"

"Madder, ribwort, elecampane and chamomile."

"Yes, yes, but what do you want them for?"

"A friend was bitten by a snake."

"Venomous? A viper?"

"Yes, but it wasn't a British snake. The wound isn't healing."

"When was your friend bitten?"

"Yesterday."

"There's a certain stone..."

"A bezoar, I know."

She licked her lips.

"I may be able to help you." She turned towards the back of the shop and Potter shook his arm, allowing his wand to slide down his sleeve into his hand at his side. She reached up and swiftly brought down a succession of jars.

"Porcupine quills, ground carnelian, madder, ribwort, elecampane and chamomile. I have murtlap essence and dittany as well."

"Brilliant," Potter breathed. "Do you sell cauldrons?"

She shook her head and backed away.

"Oh no, no, nothing like that, young master, only such things as can only be used in healing."

"That's fine, honestly. I didn't expect to get all this outside of Diagon Alley."

"Oh you don't want to go there, sir! There's only trouble to be found in that place now, you just keep away from there."

Swiftly she began weighing and packaging Potter's supplies.

"There now, that's fifteen shillings and seven pence ha'penny."

I suppressed my surprise at the price, but Potter paid up without blinking and as we walked to the doorway, he pointed his wand at her and whispered "Obliviate", then tucked the wand away again. He caught me watching and winced.

"I think she's a Squib and who knows who she might have told."

"A Squib?"

"Someone born to a magical family but without any magical powers."

"So you just wiped out her memory of our visit?"

"Yes. I hate doing things like that."

We emerged onto the bustling thoroughfare in a thoughtful frame of mind.

"A snake," I remarked and he glanced at me from beneath his untidy hair. "You have certainly had some adventures, Mr Potter."

He nodded, and I noticed that even now, he was watching the loiterers across the road, his green gaze darting about like that of a wary creature on the lookout for predators.

"Dr Watson, we're being followed."

"They may have tracked us from Baker Street," I suggested.

"The charms that Malfoy cast should have prevented them from noticing us leave; I reckon they were watching the herb shop for witches and wizards. Damn, they might even have noticed me cast the memory charm." He sighed. "I should know better than that, I've been careless again."

"You're very young to need to live under such a wartime mentality," I remarked, and he snorted.

"Yeah, story of my life. Let's go down here and shake them off."

"This is a dead-end, unless you intend scrambling over walls."

We hurried into the gloom of a narrow alley, rank with the odours of boiled cabbages and lye soap. Potter took his wand in one hand and reached out to seize me by the arm, pulling me close.

"Hold on," he said, and turned us both on the spot.

I felt as though I had been seized in a giant hand, squeezed and twisted and wrenched apart, before being thrown out again. I flailed and found myself tripping over the fire-irons in our sitting room in Baker Street.

"Sorry about that," Potter said, holding out a hand to assist me to my feet, "I'm not very experienced at side-along."

I stumbled to an armchair, my heart pounding. I realised that this was real; this was magic. Everything that had happened since I had met the three wizards, I had rationalised in some part of my mind as mesmerism or a previously unexplored effect of electricity, or sleight-of-hand, the smoke and mirrors of a stage entertainer raised to the highest level. Now I had experienced it myself and that raw, savage dislocation was nothing like I had expected.

"My dear fellow, you look perfectly white," Holmes said with concern. He himself seemed a little shaken, having seen us appear without warning upon the hearthrug. "Shall I fetch you a brandy?"

"Tea will be perfectly fine." I looked around. "Where is Mr Malfoy?"

"Upstairs, he tells me that he is preparing to 'brew'."

In the bedroom, Snape languished upon pillows, looking wan but indubitably alive. On the next bed, Malfoy had placed a plank of wood, above which floated a large, round brass pot suspended in mid-air. Beneath it, small violet flames flickered, yet the wood had not charred at all. There was a faint scent of something clean and sharp, wintergreen or pennyroyal.

"I've got dittany and murtlap as well as your shopping list," Potter remarked. "How'd you get the stuff for this?"

"Magic, Potter." Malfoy glanced at Snape, who was scowling at him. The young wizard sighed and said in a slightly less snide tone, "I transfigured the cauldron from the coal scuttle and I stuck my head out of the window and Accio-ed some basic herbs to start the base. Surprising what people grow in their back gardens and keep in their kitchens around here."

"The wizarding and Muggle worlds don't seem as far apart here as we're used to," Potter said, unwrapping his purchases and spreading the packets out on the bed. "The herb shop sold Muggle and magical ingredients; it was run by a Squib."

I watched, fascinated, as Malfoy turned a silver table knife into a sharp slicing implement with a flick of his wand and began slicing, dicing, mincing and chopping the esoteric mix of herbs. Potter rolled up his sleeves and without instruction, began to assist. I sat upon the third bed and watched.

"Are your levels of ability normal in wizards? I assume that Moriarty – Mortdelavie as you named him – is very powerful?"

"As Dark Lords go, he was almost in the same league as Grindelwald or the Dark – yes, Potter, all right, Voldemort, as far as I recall from history of magic." Malfoy tipped a spoonful of minced something into the cauldron and watched as it belched orange steam, shot through with tiny red sparks. "Add a pinch of ginger, Potter."

"I have done this before," Potter grumbled. Snape gave a little huff.

"Are you able to withstand him?" I asked.

Potter and Malfoy exchanged a glance that I could not interpret but Snape surprised me by answering in his painful rasp of a voice.

"We've little choice."

Potter nodded, Malfoy sighed without taking his attention from the pot, which now smelled of an eclectic mixture of fried fish and furniture polish.

"We'd better take him down, then," Potter said.

"Gryffindor."

"Well we had. We need to get back home and we can't do that with him popping up and trying to kill us, can we? Bugger, I think this needs pepper. Accio pepper-pot."

"Seven grains only," croaked Snape.

"Yes, sir. The madder root looks pretty old, should I increase the amount?"

"Decrease the size of the dice by a third and increase the amount by a tenth." Snape subsided into a fit of coughing and flapped a hand irritably when Potter attempted to pat his back. "You would not have lifted a finger to aid me in the past, Potter," he rasped, with the petulance of the independent man who suddenly finds himself an invalid.

"I know, sir, and now I know better, all right? You were trying to help me from the start. I'm sorry, and I know why you could never risk being nice to me, but an awful lot of your hatred was genuine."

"You did ask for it, Potter," Malfoy said smugly.

"Oh yeah, of course you were a paragon of virtue just like your father."

When Malfoy looked up, his eyes resembled chips of grey ice.

"At least I have one, don't I?"

I saw Snape's pale, thin hand curl around the handle of his wand that lay beside him. Potter stared at Malfoy as if really looking at him for the first time.

"Oh grow up," Potter said with disgust. "Your dad is an arrogant bastard who chose the losing side and my dad was a bullying git who chose the winning side. Leave it at that, shall we?"

"Two points to Gryffindor," croaked Snape.

"Only two?"

"Don't push your luck." Snape indicated the cauldron, which was boiling merrily, and Malfoy hurriedly pointed his wand at the flames, causing them to die down to a faint glow.

"You're not helping with all the house rivalry crap, Professor."

Snape stared at Potter, who stared straight back for a long moment. Then, in a gesture that held an underlying significance that escaped me, Snape inclined his head.

Downstairs, I found Holmes immersed in research, surrounded by papers, notebooks and a wreath of tobacco smoke. He waved me away when I offered to assist, so I picked up the daily paper and hid behind it while I attempted to put my own thoughts in order.

A meal of split pea and ham soup followed by steak and kidney pudding did much to lift my mood, as did the appearance after dinner of Professor Snape, weak but upright. He had removed the bandages from his throat and I was astounded to see faint silver scars where the wounds had been.

"Murtlap," Potter said, seeing the direction of my gaze. "Wonderful stuff. I reckon nothing magical would have worked without your stitching the wounds, though, Doctor." Snape hitched up his collar and scowled. Mrs Hudson had not yet been able to return his robes, so he wore clothing that Potter had purchased: a dark suit with shirt and tie. The suit fitted him as if it had been tailored for him. I recalled that Potter had bought clothing regardless of size and fit, and wondered if this was evidence of the everyday, domestic use of his magic.

"Right, nothing to do with my healing and blood-replenishing potions, I suppose," Malfoy muttered and Potter gave him a look that was both exasperated and amused.

"Not everything's about you, you know."

"Gentlemen," said Holmes, "we have much to discuss. I have found Moriarty." His statement gave rise to cries of surprise and I was gratified to see the familiar gleam in my friend's eye.

"How? He must have Muggle-repelling wards a mile thick around him!" Potter exclaimed.

"I am sure that he has, however, he has hidden himself too well," Holmes said. He offered the brandy decanter; Potter and Snape declined, Malfoy and I accepted a snifter. "I have spent the day searching for his absence, for trails that unaccountably disappear, for plans seemingly laid by others that bear the stamp of his twisted genius, in short, for a vacuum, and I have found it." He tossed down a map of southern England and pointed with the stem of his pipe. "We shall find him here."

"In Wiltshire?" Malfoy asked with his habitual sneer.

"Yes."

"Anything magical going on there is likely to be because of my family."

Holmes’ lips curved a little.

"I have found faint evidence of them too, Mr Malfoy, however, assuming that your own attitude towards 'Muggles' is typical of that of your ancestors, I have been able to discount them. They live in a vacuum as far as the rest of the county is concerned, having no contact with anyone except their own kind. Moriarty has no such scruples; he is a receiver of information and treasure from any source; things of value vanish into the rapacious maw of his desires, and they vanish around here." The pipe stem traced a circle, centred upon the edge of the Cotswolds that extended into Wiltshire. "Your family may be shielding him."

Snape stroked his lower lip with a finger.

"Is Moriarty really our problem?" he asked. His voice was deep and although still a little hoarse, held promise of appeal in both tone and diction.

"He is certainly mine," Holmes said. "While getting home again, is yours, is it not? How do you intend to do that?"

"We don't even know how we got here –" Potter began but Snape held up a hand and the young man fell silent.

"We were brought here by the power of an artefact in my possession; however it appears that the artefact remained behind at the end of the twentieth century."

"Your watch?" Malfoy enquired.

"It was not my watch. I had been asked to find it by the Dark Lord, he did not know that I had succeeded when I became ... surplus to his requirements."

"What was the watch, Professor?"

"The sister's pocket-watch."

Potter looked blank while Malfoy guffawed.

"That's a fairy-tale for little kids..." He looked at Snape and his words trailed off. "Isn't it?"

"You are the pure-blood, Draco; you know these stories better than anyone. Tell Potter about the sister's watch."

"The three brothers – do you know that one, Potter?" Potter nodded, and I thought that he looked pale. "The three brothers met Death from whom they gained the three Hallows: the Elder Wand, the Resurrection Stone and the Invisibility Cloak. What they didn't know was that their little sister had followed them and she bartered with Death. She asked for time, to try to save her brothers from their own foolishness, and Death gave to her a pocket-watch that allowed her to step into different times. However, it didn't do her any good because she must have got lost and confused and although she reappeared in the year after her meeting with Death, she came back as an ancient woman and she died of old age."

"Oh shit," Potter muttered. "Bloody sodding fuck. Sorry," he belatedly added as Holmes frowned at his vulgarity. "All I can say is, thank Merlin Voldie never got his scaly paws on that."

"Indeed. However, I had been prepared to take the risk, in the hope that he too would over-reach himself. As for the Hallows themselves...?"

Potter nodded.

"I used the Elder Wand but then I put it back in Dumbledore's tomb. I threw the Stone into the forest and unfortunately, I didn't have the Cloak with me when I went to get your body from the Shack." He grinned at Malfoy. "You never knew, but you were the master of the Elder Wand because you disarmed Dumbledore. He meant for Sna – Professor Snape to be its master but you beat him to it, then when I defeated you at Malfoy Manor, it came to me."

Malfoy gaped in astonishment, which was not an aspect of his character that I expected to see.

"You mean they're real?"

"Yup. Which means that so's Death's pocket-watch."

"We need to find it in this time-line, don't we?" Malfoy turned to Holmes, who reached for the tobacco.

"If you wish to return home, that appears to be the case."

"So you intend to assist us," Snape said, "in return for our aid in defeating Moriarty."

"You have experience in dealing with evil wizards."

"Only one and he was enough," Potter sighed.

I leaned to place another scoop of coal upon the fire.

"Well, gentlemen, where do we begin?"

Part 4: The Pocket-Watch of Death

"The Cloak came down to my father, because he was descended from the Peverells," Potter said. "The Stone was set in a ring which passed to Marvolo Gaunt, who was Tom Riddle's grandfather. Tom stole the ring from him, turned it into a Horcrux and Dumbledore got it from the ruins of the Gaunt house. Dumbledore also had the Wand, he won it from Grindelwald."

Snape nodded. Holmes and I looked at one another and I shrugged.

"None of which helps in the slightest if we want to find the watch," Malfoy said petulantly. Potter ignored him.

"The three brothers were Antioch, Cadmus & Ignotus Peverell. Antioch died almost immediately after obtaining the Wand, Cadmus appears to have either fathered a child or at least, handed on the Stone before dying, and the Cloak came to me from Ignotus' line. What do you know about the sister, Professor Snape?"

Snape turned his dark gaze onto the young man.

"She was named Zylphia and as Draco explained, she did not live long in her own time after gaining the watch. It passed to the youngest of her brothers."

Potter sat up straight.

"My ancestor, right? It didn't stay with the Cloak, though, did it?"

"No. Like the other Hallows, it disappeared from record. I retrieved it from an ancient wizard named Artorius Sparks, who was a dealer in old jewellery, clocks and watches."

"By 'retrieved' I assume you mean... ah, ok."

"How 'ancient' was this gentleman?" I enquired. "Would we be able to find his parents or grandparents today?"

"We'd probably be able to find him," Snape said, "He is a close contemporary of Albus Dumbledore, who was born in 1881. I believe that Sparks is the elder, so he is a teenager today."

"God," muttered Potter, "so's Albus." He gave a little shiver.

Snape shook his head, then winced and touched his neck. "We should not attempt to contact anyone who might meet us in the future."

"I know, Dumbledore said we mustn't be seen when we used Professor McGonagall's Time-Turner in our third year, we'd have messed up time like anything."

Snape closed his eyes, took a deep breath and muttered, "I don't want to know."

"A Time-Turner!" Malfoy exclaimed but Snape again shook his head.

"Would move us by a month or two at most and are very carefully controlled by the Ministry of Magic."

"So we need the pocket-watch, then." Potter squared his shoulders. "We need to find this Sparks bloke. Where was he when you found him, Professor?"

"He owned a shop in Knockturn Alley."

"Ah."

"Precisely so."

"He might not be there now, though, surely? Wouldn't he be at Hogwarts?"

"You might be right, Malfoy," Potter said with just enough feigned surprise to make the fair-haired wizard scowl.

Holmes looked up from his place at the dining table, where he was surrounded, as usual, by newspapers, charts and books.

"Our list of requirements stands thus: firstly, to find those of your kind who are prepared to accept our help to stand against Moriarty, or Mortdelavie as you name him; secondly, to find Moriarty himself and his minions and deal with them in an appropriate manner; thirdly to find this Sparks fellow or whosoever intends to give or sell Sparks the pocket watch, and retrieve said watch; then finally, to discover how you might return to your own world."

"And do it under the nose of Mortdelavie, who's already pretty miffed," Potter said.

"Some of us have experience of not drawing attention to ourselves, Potter."

Potter narrowed his eyes.

"I never asked to be the bloody Chosen One, did I? It was you who kept banging on about it, sir."

"While you and your little friends did everything within your power to break rules, discard advice and totally ignore direct orders, putting the lives of others on the line –"

"You're forgetting one thing, Headmaster," Potter snapped, his hand hovering over the handle of his wand, "we were kids! Don't tell me I should have been able to outsmart Dumbledore at the age of eleven, when he manipulated you into doing exactly what he wanted when you were an adult! It was Dumbledore who gave me Dad's Invisibility Cloak, who let McGonagall give Hermione a Time-Turner, who forced you to kill him and set me up to die! Stop taking your bloody resentment out on me, will you? Just because you loved my mum and loathed my dad, there's no need to – mmpf!"

Snape had drawn his wand and with a single flick of the tip, caused the antimacassar on the chair to slither around Potter's face, effectively gagging him.

"Silence, you wretched brat! Until you learn to control your mouth and your emotions, you will never –"

Potter turned his wand on the wayward furnishing, blasting the linen to a cloud of fibres as he surged to his feet. Instead of shouting back, however, he stared into Snape's startled black eyes and spoke in a level voice.

"Stop deliberately winding me up, it isn't getting us anywhere."

It seemed to me that neither man was prepared to apologise or back down. Snape was quivering with suppressed fury, refusing to do the bidding of the stripling whom he had taught, while Potter simply stood with his feet planted firmly on the hearthrug, his wand in his hand.

It was Malfoy who delicately cleared his throat and asked, "Can anyone remember how and when Mortdelavie was defeated? Because I have a nasty feeling that he didn't die at all."

Holmes diplomatically sent for a supper of tea and crumpets, the latter occupied Potter with a toasting fork and the tea had its usual effect of cheering the English psyche without inebriation. Malfoy took the hot crumpets from Potter, buttered them and passed them around.

"You are correct, Draco," Snape said over the clink of tea-spoons. "Mortdelavie simply vanished. His organisation fell apart without him at the helm and his lieutenants were killed or captured. As far as I can recall, everyone assumed that one of his people with a grudge assassinated him and Banished the body."

Malfoy handed him a crumpet and he began demolishing it in small, skilful bites.

"Maybe we did polish him off and we dropped him in a bog," Potter muttered. "Or should I say we will get rid of him. This messing with time is doing my head in; I thought the Time-Turner was bad enough. I don't know how Hermione managed it."

"That girl is an inveterate over-achiever."

"Perhaps, sir, but I couldn't have done it without her."

"What exactly did you do, Mr Potter?" I enquired. This was enough encouragement for the two young wizards to regale us for the rest of the evening with tales of monsters and heroes, mystery and magic, such I had never heard before in my life.

After breakfast, Malfoy declared that if he had to spend another day within doors, he would run mad. Holmes had already gone out early upon a mission, which, in true Holmes' fashion, he kept to himself. Professor Snape had not yet risen so I found myself the mediator in a heated discussion between the two younger men. Malfoy insisted that he needed to replenish his stock of potions ingredients from the herbalist's shop; Potter was equally adamant that he should not go alone.

"We will go out only if you can refrain from drawing attention to yourself," I informed Malfoy. I was becoming accustomed to his glower but the idea of getting out of the house had its appeal.

"I can Apparate there and back in minutes."

"Not if you don't know where it is, you twit! We'll all go, we'll dress and act as Muggles and disappear into the crowds. We could do with a brisk walk after being cooped up together."

Potter brought out the clothes he had purchased. When he and Malfoy had taken their pick of the worsted trousers, tweed jackets and overcoats, and magically adjusted them to fit, we slipped out of the back door and made our way quietly onto the swarming pavements of London Town.

Malfoy kept to his word, striding along with his hands in his pockets and head high, looking for all the world like an undergraduate on holiday.

"How much had it changed, Potter?"

"What?" Potter asked. He had one hand close to the handle of his wand and his green eyes were restless.

"London. The crowds, the smells, the shops. Had they changed very much from this, when you knew them?"

Potter pulled a wry face.

"Just a bit. Surely even you noticed the difference between a London run by horse power and one filled with petrol and diesel-driven vehicles?"

"I didn't go into Mug – ordinary London."

"Neither did I till I got my Hogwarts letter."

We paused to cross a busy thoroughfare, dodging the traffic. A short, plump woman with a heavy basket over one arm collided with Malfoy, knocking him aside. I heard the breath hiss between his teeth and his wand slid down his sleeve into his hand. I seized his wrist as the matron gasped an apology and bustled away. A street urchin darted past with a cry of "Good morning, Dr Watson!" and a cheeky grin.

"I think she was distracting you," Potter murmured, coming so close that his shoulder brushed against Malfoy's.

"The boy recognised me and so refrained from picking our pockets, I suspect that he may be one of Holmes' informants," I said.

"I damn near hexed the pair of them," Malfoy said darkly. "Blasted Muggles..."

"Temper temper, we're supposed to be blending in. Come on."

Today, the shop was tended by a much younger woman, who was more interested in catching the eye of the baker's apprentice across the road than in serving us. When I asked after the proprietor, she shrugged.

"Me Granny's got the lumbago something 'orrible. Did you say you want lovage?"

"Borage."

"Right," she said, tipping out dried herbs from a jar clearly labelled 'lovage' into the pan of the scales.

Once we had our purchases sorted, weighed, wrapped and paid for, we strolled back in the direction of Baker Street. A cold East wind was blowing with sleet in its teeth and even Malfoy's enthusiasm for our constitutional was waning rapidly. We were cutting through the maze of smaller streets between Edgware Road and Gloucester Place on our way home when we heard the sound of running feet and my name was called in a high, urgent voice.

"Dr Watson!" I turned as Potter and Malfoy both reached for their wands. The same street urchin, his face pink with exertion, came hurrying to my side. "Dr Watson, Mr 'Olmes says to tell you that 'e's found what you was lookin' for!"

Potter and Malfoy traded glances.

"Which particular thing was this?" I asked.

"'Ow the 'ell do I know? All 'e says was, 'e found it and 'e says you're to come quick, an' them an' all." He waved at my companions. "Suit yerselves, then." He shrugged, stuffing his hands into his pockets. "I ain't got all bleedin' day."

"Pockets to pick?" Malfoy drawled.

"Listen to the ruddy toff! 'Pockets to pick' 'e says, like as if e's ever had to do a day's work." The wretch pretended to duck as if Malfoy had taken a swing at him. "You comin' or not?"

"Is this a trap?" Potter breathed, as we started off in pursuit of our guide.

"It may be, except that Holmes has used the lad to run errands before now and it is his style, to give away as little as he can."

"We could use Legilimency on him," Malfoy suggested with an expression that suggested that he would rather cast a plague of boils.

"What's that?"

"Mind magic, like reading thoughts. It would tell us if he's trying to double-cross us. Hold on a minute," Potter called, breaking into a trot to catch up with the lad. "What's your name?"

"'Enry. Why?"

"We want a quick word with you."

Young Henry raised a grubby eyebrow.

"Oh yeah? Worth much to yer, is it?"

"Might be," Potter agreed.

"Awl right, mate." Henry slouched against the doorway of a large house. "Go on, then."

As Potter faced him, I caught a flicker of movement out of the corner of one eye. Even as I turned, I saw a stout arm wrap around Malfoy's neck from behind. I opened my mouth to shout a warning and something thick and damp clamped over my face, with an unforgettable sharp-sweet reek, and I knew no more.

Part 5: Kidnapped

I became aware of nausea and a thundering headache, and tried to remember if I had overindulged in the port, until the recollection of shadowy assailants brought me to my senses. I was lying in the dark, upon a cold, hard surface. As I attempted to sit up, I discovered that my hands were securely tied behind my back and my ankles bound.

"Dr Watson?" The voice was young and it trembled so much that I had difficulty recognising it.

"Mr Malfoy? Are you hurt?"

"Apart from feeling like I've been kicked in the head by a hippogriff, I don't think so. They must have used a stunning spell."

"Merely chloroform. Is Potter there?"

"Yeah, I'm here. Did they get your wand, Malfoy?"

I heard a soft grunt and the brush of cloth against the floor.

"It isn't in my sleeve so they must have it. Yours?"

"Yeah. I was on the lookout for wizards and we were overpowered by Muggles. How stupid can you get? We knew Mortdelavie operates in the Muggle world; that damn kid led us straight into a trap."

"God," Malfoy muttered, "I wish I had an anti-nausea potion. I feel vile."

"An unfortunate side effect of anaesthesia by chloroform," I informed him. "Try not to think about – oh."

The smell and sound of emesis were sufficient to bring about the same result in Potter. I was powerless to assist them, battling my own queasiness and on the alert for the arrival of our captors. I shuffled away from the two youths, discovering that we had been cast upon the damp stone-flagged floor of a small room. A faint outline of grey indicated where a high window was boarded up or shuttered against the daylight.

One of the young wizards coughed and spat onto the floor.

"Manners, Potter."

"Oh shut your face, we're all in the same boat here."

"Be grateful that we were not gagged," I said. "You would have had to either swallow or allow the vomit to escape through your nostrils to avoid suffocation."

"Eurgh! That's disgusting."

"Gentlemen, we could be in deep trouble, for I suspect that we are awaiting the arrival of Moriarty himself. Tell me, is a wand essential in order to perform your magic?"

"Yes," Malfoy replied at once.

"Not always," Potter said with more hesitancy. "I did accidental magic before I came to Hogwarts, but it was totally out of control."

"Of course you had to be special, didn't you?"

"Mr Malfoy, is this really the time to air childish resentments?"

There was a pause, and then Malfoy muttered "Sorry," just loudly enough to be heard.

"I've managed to work minor spells through my wand when I wasn't touching it, but I was quite close to it at the time," Potter mused.

"What would happen if you believed that it was close, but it wasn't?"

"No idea, I've never tried. No time like the present, I suppose. Lumos! Wingardium Leviosa! Nope, not a thing."

"You weren't really focussing."

"Right, Malfoy, you try it then if you're so –"

"You were saying it as if the wand was still there to do the focussing for you. That's what a wand does; it acts as a focus, like a lens, and directs and amplifies your inherent magical power."

"So what do you reckon we should do, then?"

"Find something else to act as a focus."

"Like what?"

"Something magical, I suppose. Have you anything magical with you?"

"No, I was only carrying my wand. You're the one who goes around with galleons and signet rings and magical paraphernalia. I didn't even have my pocket-watch with me, I was only expecting to bring Snape's body back, not go traipsing across a century."

"They took my money –"

"Hush!"

We could hear rapidly approaching boot heels striking on stone. A key rattled in the lock and the door was thrown open. Sullen lamplight outlined the figures of three men, and then one of them lifted a lantern. My heart, already beating fast, speeded up as I saw the ruffianly aspect of our captors, their slovenly dress and gloating expressions. Any thoughts of appealing to their better natures vanished as they swaggered into the room.

"Afternoon, gents! Enjoying your stay in our salooo-brious accomy-dation, are we? Nuffink to say for yerself?" The largest of the kidnappers aimed a casual kick at Malfoy, who wriggled out of his path. The thug sneered, seemingly inured to the venomous expression in Malfoy's grey eyes.

"Filthy little bugger," remarked his companion, having accidently stepped in one of the pools of vomit. "Ought to make 'im clear it up."

"Wiv 'is tongue, right?"

The third man, the one holding the light, stared down at Potter.

"Oo are you? We knows all abaht 'im –" indicating me with his free hand, "but oo're you?" When Potter did not immediately respond, the largest man drew back a foot and kicked him, hard, in one knee. Potter grunted in pain and gasped out "Cedric Diggory."

"Diggory. And oo're you, fancy boy?"

Malfoy did not give him time to lash out.

"Vincent Crabbe."

The big man sniffed and wiped his sleeve across his nose.

"Reckon they're lying?"

"Yeh."

With the casual arrogance of the habitual bully, he reached down, picked up Potter by the collar and punched him in the ribs. The smaller thug placed the lantern on the window ledge and rubbed his hands together in anticipation.

"Bastard!" Malfoy snarled through his teeth and I suppressed a groan. They wanted us to react, to attempt to fight them and give them all the more reason to beat us.

"Did we hurt yer likkle sweetheart, then? Oh dearie, dearie me; whatever shall we do?"

Potter was thrown aside and all three turned to surround Malfoy, their crooked, rotted teeth exposed as they leered. As the first boot landed and the young man curled up in an attempt to protect his vulnerable abdomen, the lamp flared up and a ceiling beam fell into two pieces with a mighty crack and crashed to the floor, narrowly missing Malfoy and pinning the big man by the foot. He screamed in rage as his companions scrambled to the doorway.

"Come back 'ere you stupid buggers! Ow, get it orf me!"

"Not bleedin' likely!"

With a bellow, the man heaved the beam aside and lurched to his feet, groaning and staggering after the others.

"You'll wish you were never born when the top man gets 'ere! Ee'll flay the skin of yer bones an' I'll larf as 'ee does it!"

The door slammed and we stared at each other in the flickering lantern light.

"Nice one, Potter," Malfoy said eventually. "I suspect that means they've gone to fetch Mortdelavie."

"That was going to happen anyway."

"I see what you mean about the accidental magic; we're lucky the entire ceiling didn't cave in."

"I said it was out of control."

"It impressed those three fools; do you think you can hold off wizards?" I asked.

"No, they'll have wands; I can't fight them without my wand." Potter slumped down on the floor and let out a long breath. "You hurt, Malfoy?"

"Bruised. You?"

"The same. They've done something to my knee; I hope we don't have to run for it."

"Chance would be a fine – can you hear anything?"

This time, the footsteps were light and quick, and the lock clicked gently. We turned towards the doorway and subconsciously moved closer together, then stared in disbelief.

Two women, one short and plump, the other old, stooped and gaunt, stared down at us. I recognised the matron who had collided with Malfoy earlier in the day; she even carried the same basket over one arm. The crone also had an air of familiarity about her although I could not immediately place her; her face was almost hidden in the shadows of her old-fashioned bonnet.

"Oh my word," the plump woman said. "Are you all right, my dears?"

"We would be very grateful if you could remove the ropes binding our hands and feet, Madam," I said.

"Swiftly, swiftly," cried her friend, in a cracked, quavering voice.

"Of course, lovey. Just a tick." With that, the lady brought out her hand from beneath her shawl, raised a wand and waved it with a whisper of "Relashio!". The ropes dissolved away from my wrists and ankles and I clambered to my feet and went to assist Potter, who rubbed his knee and grimaced when he tried to stand.

"I don't know who you are, Madam, but we're grateful to you."

"They're coming!" croaked the crone, staring back out of the doorway.

"We need our wands."

"I hope you'll have them back shortly. Now hurry!"

We followed the two women out into a low basement, and up a creaking wooden stairway, Potter leaning heavily on my arm. We emerged through a doorway into a gloomy space that smelled like a riverside warehouse, to be met by indistinct figures pointing their wands at us.

Our homely saviour cast aside her basket and brandished her wand with a cry of "Expelliarmus!"

There followed a few moments of terrifying and frantic activity. Fire flared from the tips of wands all around us, causing the old lady, Potter, Malfoy and myself to dive for cover behind a stack of barrels. The aged woman groped in her petticoats and to my amazement, brought out a revolver and took aim. Her very first shot hit home, bringing down one of the wizards clutching his shoulder.

"She can't take them on alone," Potter said, as the plump little witch was beaten back. She cast a filmy shield between herself and our enemies, against which the multicoloured spell-fire rebounded, but it was clear even to me that she was weakening rapidly. They were too many for her, and after our first success, it appeared that the wizards were able to repel bullets, although the old woman's aim was excellent and she kept at least three of the wizards pinned down and unable to bring the full force of their spells to bear upon our unlikely saviour.

Favouring his injured leg, Potter ducked out of our hiding place to scramble to the side of our champion. He said something to her, reached up and clasped both hands over hers, upon the handle of her wand. The tremulous mist of her shield spell immediately brightened and expanded, into a glowing hemisphere against which the fiery spells splashed harmlessly.

"A focus, of course," Malfoy said, turning towards the old woman. "You don't have a wand as well, I suppose?"

In the shadow of her bonnet, I glimpsed a hooked nose and bright, deep-set eyes, and she spoke in a voice that I knew well.

"Unfortunately, Mr Malfoy, I am but a Muggle."

"Holmes!" I gasped.

My friend took aim and loosed off another shot, causing an inattentive wizard to jerk back with an exclamation of annoyance.

"I pray that our friends can do more than merely hold them off, they have us pinned like fish in a barrel here. Can you assist them, Mr Malfoy?"

"Not without a wand."

"Mrs Prewett's wand must suffice, then."

Holmes nodded towards the witch and Malfoy, after a second of hesitation, went to join her, placing his hand upon Potter's and adding his power to the shield, which again strengthened perceptibly.

"Well, Watson, you led us a pretty dance, I feared we would not reach you in time." Holmes squinted along the barrel of the revolver then lowered it again, loath to waste the ammunition upon wizards who seemed protected against the bullets, at least while they were concentrating upon us.

"The lad, Henry, betrayed us."

"Not deliberately. Mrs Prewett informed me that he is a Squib; he has no magical ability and was unable to withstand magical commands from a wizard. Moriarty makes use of a mix of Muggles, Squibs and wizards, which is his strength. Henry was commanded to lead you to Moriarty's gang of cut-throats and he was unable to disobey."

"They took us completely by surprise and used chloroform to subdue us."

"Ah, I suspected as much. It appears even wizards are susceptible to such chemical weapons."

"They're almost helpless without their wands."

"I hope that the question of the wands – good God!"

With a crack and a blaze of curse-light, another wizard exploded into the cavernous room. A slender figure clad in black, he cast spells faster than the eye could see and the others fell back before the ferocity of his attack. I saw a man flung aside with his torso torn open, another screamed and clutched his bleeding face. In the momentary hiatus created by his arrival, he flung two slivers of wood past the edge of Mrs Prewett's shield spell. Holmes scooped them up and leaped forwards.

"Your wands, gentlemen!"

Potter and Malfoy seized the wands and immediately ran to stand beside their Professor; indeed, for it was Snape who held a dozen fighting wizards at bay, Snape whose magic had saved us, Snape who now swayed pale and shaking at the limit of his strength.

"Apparate," he gasped, "Mortdelavie's coming. Take Holmes and Watson home, hurry up!"

Malfoy reached out, seized Holmes' arm and spun on the spot, disappearing with a sharp report.

"Mrs Prewett, join us in Baker Street; Potter, take Watson and go!"

The homely little witch turned and vanished, her shield disappearing with her. Snape threw a couple of wild bolts of fire at random and Potter grabbed my wrist. As Potter raised his wand, we saw Snape sink to one knee, eerie multicoloured light coruscating around him.

"Snape!" I cried and I felt Potter brace himself against me.

"Accio Snape!"

As if an invisible hand dragged him, Snape hurtled towards us and I automatically grasped him as he collapsed against my shoulder. Potter seized us both and I felt that wrenching sense of dislocation, the warehouse vanished and we were once more in our familiar rooms in Baker Street.

Hardly had I eased the pale and trembling Professor onto the sofa and reached for the brandy, when there was a soft but penetrating sound, like a bell. Potter and Malfoy faced the door, shoulder to shoulder, their wands at the ready, only to lower them as Mrs Prewett hurried in.

"Oh what a day!" she exclaimed, patting herself upon her ample bosom. "It's quite all right, my dears, 'tis only me. Are any of you hurt?"

"Professor Snape is exhausted," I said, holding a glass of brandy to his lips. "That's it, my dear fellow; a couple of sips will help. Mr Potter's knee is injured; I will bind it in a moment."

"No need for that," the lady said, brandishing her wand. "Which one is it, young man? The left? Roll up your trouser, that's the way and hold still..." She whispered a series of sentences in Latin, too fast for me to catch, and Potter grinned and gave his leg an experimental shake.

"That's terrific! Much better, thanks very much."

"Anything else?"

"Malfoy was kicked in the ribs."

Malfoy untucked his shirt and pulled it up to expose a big contusion. I hurried over to watch as she healed the young man's side, tracing the tip of her wand over the damaged flesh and murmuring words under her breath.

"My profession might soon become extinct, if there are many around like you, Madam," I remarked.

"I doubt it, Doctor. Ah, Mr Holmes, you're back with us!"

Holmes emerged from his room, having discarded the bonnet and skirts, shawl and warts of his disguise.

"We haven't been introduced," Malfoy said. "Madam, Draco Malfoy at your service."

"Delighted, I'm sure. Malfoy, you say?" She narrowed her eyes at him. "One of the Wiltshire Malfoys?"

"He isn't a Dark wizard," Potter assured her quickly. "Sorry, I'm Harry Potter and that's Professor Severus Snape, whom you already seem to have met."

"Mrs Jenny Prewett. Most of the Malfoys are all cheek by jowl with Mortdelavie as far as I'm aware. The Potters are a fine family but I know of no Snapes..."

"You won't. He's a Prince on his mother's side. Look, this is very complicated, but we've been out of the country for a long time, we don't really know what's going on."

"Well, I take people as I find them, and I certainly found you on the wrong side of Mortdelavie, didn't I? If it hadn't been for your friend Mr Holmes, you would be dead."

"I'm surprised that Holmes and I have lived as long as we have," I remarked.

"He preferred to leave you both where he could keep a wary eye upon you. Mr Holmes was a most credible witness to his death; why should anyone doubt the word of Sherlock Holmes? The Muggle authorities are convinced that their 'Moriarty' is dead and gone. Besides, killing Mr Holmes would attract too much Muggle attention as well as gain him other powerful enemies; we're wary of Mr Mycroft Holmes and there are a few wizards and witches who are in your debt, Mr Holmes: they would seek to avenge your death. Not all of your clients have been Muggles."

"Hah! Why does that not surprise me?" Holmes frowned, and I knew that his formidable intellect was focussed upon the past, assessing his clientele in light of this new information.

"Mrs Prewett," Potter said thoughtfully, "how did you get in? Malfoy and I put wards around the house."

"Wards? I thought you just had warning charms. I felt hardly any resistance at all."

Malfoy weaved a series of swift passes with his wand and swore softly.

"They've been dismantled while we were out; we're sitting ducks."

For a frozen moment, we stared at one another, then there came the gentle sound of chiming bells.

Before anyone else could speak, Potter snapped out a command.

"Malfoy, summon the potions for Snape. Watson, Holmes, anything you need to take with you?"

"My medical bag and my revolver and bullets."

"Accio Watson's gun and ammo, Accio Watson's bag!" Potter held up his hand and my revolver slapped into his palm. My black bag flew across the room and he thrust everything into my arms. Holmes tucked his own weapon in his pocket and pulled on his overcoat, as Malfoy called for phials of his medicines for the Professor.

"Go," Potter snapped. "Mrs Prewett, leave now!"

"You need to hide," that feisty lady said. "I can help you."

The front door slammed open downstairs and Potter nodded.

"Fine. Apparate to Kings Cross station, we'll meet you there. Can you side-along?"

"Of course, dear."

"You take Mr Holmes. Malfoy, take Snape, I'll bring the doctor. Go!"

I caught a glimpse of Moriarty's snarling visage as Potter magicked me away from my comfortable home, into the bustle and noise and smoke of the great railway terminus.

Part 6: Flight to the Underground

"Why here?" I enquired as we picked our way past piles of luggage.

"Only place I could think of that we'd all know. London changed so much by our time. These little steam locos are amazing... ah, there's Mr Holmes." Potter indicated my friend, whose height made him stand out amid the family groups who huddled together against the wintry chill. Mrs Prewett beamed up at us as we approached.

"I think I saw your friends over by the station buffet. A nice hot cuppa would go down a treat with me, that's for certain."

We found Professor Snape leaning upon Malfoy's shoulder, while the latter sifted through the little bottles in his pockets.

"Here you are, sir, here's the strengthening potion. Good job I made a double batch."

Snape gulped back the viscous fluid and I thought for a moment that I saw wisps of steam floating up from his ears. Potter was staring around, fascinated by the great snorting monsters of the steam locomotives.

"There now, all set? I was just thinking how much I would welcome a nice cup of tea –"

"Mrs Prewett," Holmes said quietly, "it is my belief that Moriarty may have heard Potter's instruction to come here."

Her mouth made a little round shape of alarm.

"Oh my. Yes, then we'd better hurry, hadn't we? Oh dear." She frowned. "If I could only get a message to Agrippina, I'm sure she would know what to do, but an owl would take too long."

"Can't you send a Patronus?" Potter asked. The little witch blinked up at him.

"I could try, dear, but that's a pretty tricky spell, you know, not easy to cast under pressure."

Snape caught her by the elbow and we all followed them into a quiet corner behind a stack of trunks awaiting the attention of the porters.

"I'll send one. What's her name and what's the message?"

"Agrippina Calloway. Tell her that Jenny Prewett says the death of life is on my heels at Kings Cross Station and I've brought friends who're unable to Apparate."

Professor Snape raised his wand, his face a mask of concentration. A great burst of silvery light flowed from the end of his wand, coalescing into the shape of a deer, which stood in silence, bowing its head as he spoke quietly into its ear. Then it bounded into the air and vanished.

"Well, you're a caution and no mistake, producing a true corporeal Patronus under pressure, taking on a great army of wizards single handed –"

"What is your friend likely to do?" Holmes asked, cutting through her paean of praise.

"She'll know, Mr Holmes, never you fear!"

"Yes, yes," snapped Holmes, "but we need to know what we should do next! Will she appear in our midst?"

"Oh, I see. No, I expect she'll have a look around first, see how the land lies. We'd best stay here out of sight."

I leaned against the wall. The effects of the chloroform still lingered and my head-ache was fierce. Someone nudged me and I looked around at Malfoy, who held three phials of potion in his hand.

"It's all right," Potter told me, accepting one of the little bottles. "It tastes foul but it works, believe me. He's good at potions and it's not in his interest to poison us."

Malfoy gave him an incredulous look as I downed the evil-tasting brew. I was assailed by a wave of giddiness, then the world settled back into its place, this time without the head-ache and lethargy; in fact I felt better than I had in weeks, even losing the residual tightness in my chest from my bout of bronchitis. Malfoy waved away my warm thanks but he coloured slightly.

"You can brew potions too?" Mrs Prewett said eagerly, "all of you?"

"Malfoy's very good," Potter told her, looking at Snape. The Professor returned his stare with a sardonic tilt to one black eyebrow. "But Professor Snape's a potions genius."

"My, my! And what about you, young Mr Potter? What do you do best?"

Potter opened his mouth but it was Snape who spoke first.

"Potter lives to irritate me."

To my surprise, Potter merely shrugged.

"Just glad you're still here to be irritated, sir."

A boy of some twelve years of age, muffled in a coat that was rather too large for him, dashed past our hiding place, skidded to a halt and returned to stare up at us out of brilliant blue eyes.

"Blimey, there you are! Started to fink they'd got yer. 'Ello Mr 'Olmes." He had all the cheeky alertness of one of Holmes' Baker Street Irregulars.

"Good afternoon, Cuthbert," Holmes replied. The lad gaped at him,

"'Ow did you know?"

"Bert," laughed Mrs Prewett, "This is Mr Sherlock Holmes you're talking to!"

"But 'ee's a Muggle and 'ee recognised me through Mrs Calloway's glamour!" Holmes merely smiled enigmatically. Young Cuthbert turned to Mrs Prewett. "Mrs Calloway says the 'ole station's surrounded and they're putting up anti-wotsit wards. She can't git in so you'll 'ave to git aht. She says she'll meet you at the deep underground."

"Oh dear!"

"Anti-Apparation wards?" Snape asked.

"Yeah, them."

"Are you able to make this Apparation to or from something moving, such as a train?" Holmes enquired. Snape spun to face him.

"From a speeding train is relatively easy, onto one is another matter. If we are all under Disillusionment charms, we can leave the station by train, then once outside their wards, we will be able to Apparate."

Snape raised his wand and tapped me upon the head. I felt a trickle of something cold spilling down over my entire head and body. I saw Holmes' eye widen, then the Professor turned and did the same to him.

Where my friend had been standing, now appeared a plump, vague-looking fellow in a vicar's black cassock and cloak.

"Cor, you're as good as Mrs Calloway!" exclaimed the young rascal.

"I've had a lot of practise," Snape said dryly, turning his wand upon himself. The vicar now acquired a curate. Once Malfoy, Potter and Mrs Prewett were transformed (we took on the appearance of a group of travelling clergymen, one accompanied by his wife and son) we hurried onto the next train awaiting departure.

"How did you recognise young Cuthbert?" I enquired of Holmes as we settled ourselves into a compartment. It was strange to hear Holmes' clipped, incisive tones issuing from the bland face of the clergyman.

"Everyone wears out their boots in a slightly different fashion. Knowing what I know now about the abilities of our magical brethren, and hearing a voice that I recognised, I glanced down and noted the pattern of wear upon young Bert's boots. He appears to straddle both worlds, I assume that Henry does likewise."

"'Enry Kirby, the Squib?" Bert asked. "Yeah, him and me work together sometimes, 'specially when we're running errands for you. Mrs C likes to know what you get up to, Mr 'Olmes!"

"Who is this lady?" I asked.

"The leader of the resistance against Moriarty," Mrs Prewett said. "That devil, he killed her husband when he tried to stand up against him a year back. He left her alive; to carry a warning to the wizarding world that he wasn't to be trifled with, not imagining that he'd made an enemy as ruthless as any Boadicea!"

I asked Holmes how he had found us when we were captive in the warehouse.

"I was out and about in the disguise that you saw. Although 221b was under surveillance, those watching had clearly had orders to concentrate upon certain people and an unappealing old woman collecting the laundry was beneath their notice. I was on the way to meet my young informants when something very strange occurred; a silvery deer, like the ghost of a doe, appeared and spoke to me in Professor Snape's voice, informing me that you, Watson, plus the two younger wizards, were missing. Clearly it was the 'Patronus' that Professor Snape later demonstrated so ably. I took a few moments to send a message to the Irregulars, telling them to seek you out, before hurrying home."

"I got the message," Bert interrupted. "And I passed it on to the uvver boys and Mrs Prewett."

"You bumped into me," Malfoy remarked.

"I did; I wanted to confirm what I suspected, that you were one of the missing wizards. I saw the end of your wand in your sleeve. When young Henry went off again, I didn't think any more of it, not realising that he had been sent to lead you three into a trap."

"I found 'im in a state, 'e was all 'ot and bovvered and Confunded but 'e couldn't tell me anyfink so I found Mrs P and she went off again as soon as I told her."

"I could have kicked myself," the matronly witch sighed. "I should have followed you myself. I thought two wizards would be reasonably safe out in the town."

Snape snorted softly and folded his arms.

"Trouble magnets, the pair of them."

"That's it really. I rushed over to Baker Street, told Mr Holmes and Professor Snape what I suspected had happened, waited until the lads brought word of where you were and then we came to get you. I must say, I haven't seen anything like it; Professor Snape fought for you like a tiger."

Snape inclined his head politely at her words. Malfoy smirked at his teacher, while Potter said, "Yeah, he always does."

As the train picked up speed, Mrs Prewett pointed out a small public park and we agreed to meet there in a few minutes. She seized Cuthbert by the arm, turned on the spot and they vanished, to be swiftly followed by Snape with Holmes, Malfoy alone and lastly, myself in the capable hands of young Mr Potter.

Potter and I both struggled to keep our footing, going instantaneously from a fast-moving train to a static gravel path. He had placed us in the shadow of a large plane tree, but even so, I was surprised that the passers-by appeared oblivious to our arrival. He grinned at me and nodded to the other side of the park, where our companions were emerging into a side street.

"That went well," Malfoy remarked. "With luck, they'll be searching Kings Cross for a while before they cotton on."

"All the more reason for us to hurry," Professor Snape snapped. Mrs Prewett nodded.

"Yes, yes, we need to go to the Elephant and Castle."

"The pub?"

"No, Mr Potter, the underground railway station."

"Is that the deep underground where we're to meet your friend?"

"It is one of the ways in. Our headquarters are very heavily protected!"

"Like Gringotts," Cuthbert said happily, trotting alongside our guide as she set off at a brisk pace.

"Well I broke into Gringotts, so let's hope it's even better."

"An' you got aht again? Bleedin' 'ell – ow! Me ear!"

"You mind your language, young man."

"Yes, Mrs P. Sorry."

She led us through streets I had never seen before, and I pride myself upon my knowledge of our capital. At the station, there was a brief pause when we discovered that we did not have the required two pence each for the turnstiles. Malfoy simply twitched his wand in the direction of the turnstiles and muttered "Accio fourteen pennies" and handed out the coins that appeared in his hand.

We boarded the small, claustrophobic carriage in the next train towards Kennington, sitting together on the bench seat opposite a gaggle of schoolgirls with their stern mistress. Mrs Prewett whispered quietly then said in a conversational voice "There, I've put up a silencing charm. We'll need a big disillusionment charm to stop them noticing us when we Apparate out – thank you, Professor Snape. Now, get ready. As soon as we've left the station, everyone wait for my signal and Apparate ten yards to your left, facing forwards."

"Apparate blind?" Malfoy gasped," Through the wall of the tunnel?"

"Yes, the only way through the anti-Apparation wards is from this direction. Ready?" She seized Cuthbert's hand, I felt Potter's fingers fold around my wrist and Snape grasped Holmes' shoulder, then, seeing Malfoy's stricken expression, Snape reached out with his free hand and pulled the younger man to his side. On Mrs Prewett's nod, we popped out of existence and whirled through the void, emerging in complete darkness and the distinctive earthy scent o