"Who gave Sherlock Holmes a megaphone?" Sally is asking, as you walk up to the police tape that marks the perimeter.

These are the sorts of questions you gave up wondering years ago: that way lies a particular kind of madness.

Besides. There are more immediate issues to focus on - specifically, the ten frightened hostages and the unstable man holding them all at gunpoint. Sally has yet to learn to let go of the trees in order to see the forest. You don't have time to worry about Sherlock, who now stands to your right, still clutching that blasted megaphone and peering intently through the restaurant windows.

"I mean, where did the freak even find a megaphone?" Sally repeats, not even trying to keep her voice down. You remind yourself you are due to have another talk with Sally about showing professional courtesy to Sherlock. Her insults are becoming increasingly pointed, and even though Sherlock, for the most part, ignores them, it's not proper.

"I'm sensing some real animosity between those two," a man murmurs from directly behind you. It's not a voice you recognise and you whirl around, because this perimeter has been set up for police only. You are about to demand to know what he is doing here, but he beats you to it - gesturing towards Sherlock. "I'm with him."

"He is not," Sherlock contradicts (and, bizarrely, you are put in mind of one of the more humiliating press conferences of your life, the sound of a dozen text tones all signalling the arrival of the same message: wrong). It’s nice not to have the full force of that cool disdain aimed in your direction.

"Fine," the man concedes. He’s an American, judging by his accent. "I’m not with him. But I do have someone in there, like he does."

You look to Sherlock again for an explanation. He nods his head, slightly. "John is inside," he elaborates. "Mr West is permitting us to communicate through him."

"And Gus!" the man says. "Don't forget Gus, Gus is inside too. Communicating," he says, emphasising the word.

You don't know who this Gus is, but you doubt he'll be as cool in a crisis as John Watson - few men would be, and if this man’s temperament is anything to go by, his friend could make the situation even more volatile. "If you have a friend in there, that's even more reason why you can't be involved," you say. "You need to leave - now. Sherlock, come with me."

The man doesn't move. "Why doesn't he have to leave?"

"Sherlock consults with us on cases," you grit out.

"I do, too," the man says. "I work with the police all the time, back home. I can help."

"Sorry," you say, rubbing your temple, "who exactly are you?"

*

As it turns out, he is Shawn Spencer, American psychic detective extraordinaire, and despite the migraine you can already feel coming on, the whole unfolding sideshow is almost worth it for the expression of distaste on Sherlock's face when Shawn launches into a detailed summary of his own omniscience.

"You're no more psychic than I am," Sherlock says dismissively.

Shawn grabs his arm. "Could it be you are a fellow clairvoyant?" he hazards.

"Clairvoyancy - is that what passes for observation in America?" Sherlock asks, clearly already bored of this conversation. He looks Shawn up and down, once. "You're a two-bit charlatan."

Shawn looks intrigued. "Hey! That's insulting. I'm insulted. Wait, do I challenge you to a duel now? I've heard stories about you English."

You clear your throat pointedly, and Shawn looks at you, and then the restaurant with the ‘closed’ sign in the window. “Oh, right. Fight crime now, duel later. Got it.”

"You've still given no evidence to justify why your presence here is warranted," Sherlock says, in clipped tones.

Shawn suddenly lets out a low cry and crumples to the ground, flailing his arms in a series of strange jerking motions. Sally looks to you for direction, and you shake your head. For one thing, you had a cousin who used to have seizures, and her contortions looked nothing like this. Also: Shawn looked behind before he threw himself to the ground.

Eventually, Shawn claws up a spasming fist and beats the air, blinking up at the assembled expressions staring down at him before fixing his gaze firmly upon you. It's more than a little unnerving. "The spirit world senses your doubt, and would like to provide you with assurances. I'm sensing... that you are a dedicated detective," Shawn intones earnestly. "The spirits of all those you have helped bring to peace would like me to thank you." You resist the urge to roll your eyes. "You've been a detective at Scotland Yard for seven years now. You are in a relationship, although your devotion to your work makes this problematic. Your sister had her first baby this week, and you visited her at the hospital. You recently gave up smoking, although you continue to carry a pack of cigarettes as some sort of sado-masochistic test of will-power." From behind you, Sally tries to suppress a snort of laughter, without success.

Shawn levels a cocky grin as he rises to his feet. "Impressed?"

You'd be more impressed if Sherlock hadn't done virtually the same thing - minus the psychic pseudo-seizure - the day you first met him. Still, you try to summon up a measure of the same wonder you felt back then to placate Shawn now. If he's anywhere near as talented as Sherlock, you will no doubt be relying on his help soon enough. "Amazing," you say, and as it turns out you don't need to feign the shock in your voice after all, because it's just dawned on you: there's two of them.

Heaven help us all.

Sherlock sniffs. "Child's play." On anyone else, it would sound like jealousy, but the words spoken in Sherlock's voice are merely a statement of fact. You wonder, not for the first time, what Sherlock was like as a child - you can't help but picture him exactly the same as he is now, only shorter, hair even more unruly, eyes alight and burning to see everything.

Shawn turns to face Sherlock, straightening up to his full height - which is still an inch or so shorter than Sherlock. "And you -" he says, jabbing a finger in Sherlock's general direction - "you play the violin, dabble in illicit substances and terrible experiments, and have one brother - older than you, I'm guessing. Your shoulder is still recovering from a recent confrontation, likely involving explosives. You live not far from here - central London. Also, you had porridge for breakfast, because you were out of eggs - although your flatmate does all of the shopping, so you shouldn't really complain, although of course you still did,” Shawn concludes, something like triumph in his voice. “I am right, aren't I? The spirits are never wrong. Do you believe me that I’m psychic now?”

“You are almost entirely correct,” says Sherlock. “And still absolutely a fraud. I can infer the same set of information from you, without reliance on any supernatural force. For instance: I know you are impulsive and frequently act without consideration of possible consequences. You disguise your natural intelligence behind obscure references, ridiculous play-acting and your own personal brand of bravado. You have a strained relationship with your father, who, until his retirement worked in a senior law enforcement role, and you remain overly invested in the life of your best friend, with whom you are flying back to America two days from now.”

"How did you - oh. Gus' bag," Shawn says, under his breath, and then, louder: "Wait, I’m sensing something else: you were in the restaurant right before this happened. Did you know this was going to happen?"

Sherlock doesn't answer, just presses his lips tightly together, but his silence speaks volumes.

"Sherlock," you reprimand, because John's not here to say it.

“There wasn’t time to call the police,” Sherlock says. “Besides, this seemed the most efficient solution.”

Sometimes you wonder if it would be easier to distrust Sherlock the way Sally does – because then you would have nothing to lose, as opposed to right now, with ten hostages lives on the line. You hesitate. You know what protocol says you should do.

Hang the book, you think. Sherlock solves things faster than you and your entire police force. Even if he’s the one who allowed this mess to occur in the first place, somehow you remain blindly optimistic that he still has it within his power to set it right, in a way that doesn’t require the disastrous combination of brute force, a nervous finger on a trigger and ten terrified hostages (well, nine if you subtract John Watson, whom you freely concede it would take much more than West to terrify).

"For your information," Sherlock says, staring straight ahead, "I do shop for groceries. Ocassionally."

Shawn smiles.

*

Once they reach West's apartment, it’s amazing to watch how quickly they get down to business.

"And the cat would - "

"Yes, but on this occassion - "

"Oh, of course, the butter jar - "

"Six would have done it, I think."

Sherlock looks at him for a moment, as if assessing. When he finally speaks, all he says is “Quite so,” but Shawn beams as if that’s a compliment, and you suppose it is.

You stand there, trying to be patient at the volley of seeming nonsense, waiting for them to tease out the tangles and sort through the snarls until they can present to you the mystery, unravelled and so obvious once examined in its entirety.

As usual, you suppress the fleeting jealousy that Sherlock can do in a matter of minutes what would normally take days to puzzle out through the usual channels of police procedure and standard observation.

Sherlock clearly doesn’t believe Shawn is psychic, and you find you don’t either, really, although you let the polite fiction stand for the same reason you imagine his police liaisons back home probably do – it’s easier, for the both of you. Shawn has somehow stumbled upon a way to excuse his abilities, something Sherlock has never felt the need for.

You wish Sherlock was psychic. It would be easier if the source of his innate talent had its roots in the supernatural rather than the preternatural.

*

Yet another volley of insults has erupted between Sherlock and Shawn- over the pronunciation of alabaster, of all things - with Shawn insisting that he's heard it both ways. Discretion being the better part of valour and all, you pretend you can't hear them.

Until -

"You agree with me, don't you Lessie?" Shawn asks, and suddenly wilful ignorance is no longer an option.

"What did you just call me?"

Shawn has the grace to flush. "Sorry," he says. "Old habits."

"It's Lestrade. Les-trade." You place definite emphasis on each syllable.

Shawn nods enthusiastically. "It is," he agrees. "Lestrade. Is your name. Absolutely it is."

Then: "Do you like pineapples?"

You rub your eyes tiredly and wonder when, precisely, this became your life? When you look up, you realise you are the focus of attention - and you remind yourself it's not your imagination: they probably actually do know exactly what you are thinking. You say it anyway. "You're both mad."

"Sometimes," says Shawn. "But at least we still know our hawks from our handsaws." You would retort but you're actually impressed - Shawn's conversation has been liberally sprinkled with pop-culture references, but this is the first literary allusion - and Shakespeare, at that. Of course, he rather spoils the effect the next moment, when he rubs his hands together and starts cackling.

"Oh for heaven's sake," you say.

Sherlock is tapping out another text message on his phone, and for a moment there, you'd swear to the fact that he's actually smiling.

Almost instantly, his phone chimes. "Is that John?" you ask. "What did he say?"

"Nothing relevant," Sherlock says, sliding his phone back into his jacket pocket.

You half expect a retort from Shawn, but when you look up you realise he is now standing in the doorway flirting outrageously with Sally, who is staring at him in amused disbelief.

*

After leaving West's apartment, you return directly to the restuarant, where West still holds the hostages captive.

"So he really is the killer," you confirm. "There's no conspiracy."

"None at all," Shawn says. "West here has been off his meds and off the reservation for quite some time, judging by what we found in his apartment." He adds belatedly: "And his aura, of course."

"Of course," you say, leting the aura comment pass unchallenged. "What will you tell West?"

"Exactly what he wants to hear," Sherlock says. Shawn is already typing a message on his phone, and sure enough a few moments later the first person emerges from the restuarant, blinking in the bright London sunlight. You count the hostages as they file out: six, seven, eight. Still no sign of John Watson, or Shawn's friend Gus.

"Right," you say, "thanks very much, we'll take it from here," and you signal to the officers that have been on standby for the last half-hour. When you burst into the building, it's the work of a moment to disarm West. Somehow you're not surprised to find that Sherlock and Shawn followed your officers into the restuarant, nor surprised to see them rush to John and Gus' side, respectively.

Shawn has a brief arguement with his friend, before they exit the restuarant, door chiming softly in their wake. Sherlock and John leave soon after, Sherlock launching into an impression of Shawn on his way out, to John's obvious amusement.

You'll be here for awhile yet, overseeing statements to be taken from the remaining hostages, but as the former hostages in question are all very much alive, you can't find it in yourself to feel too aggrieved.

*

The next day, it's a new case, and you stand over today's victim knowing what the next logical step is. Still, your finger pauses for a moment over the 'call' button on your phone - long enough that Sally looks up, noting your hesitation.

"It was easier," you say, nonsensically.

"What was easier?" Sally says.

"When there was just one of him."

She nods her whole-hearted agreement, but you know she doesn't mean it the way you do. You used to comfort yourself with the fact that Sherlock was – not a freak, in the way Sally means it, harsh and bitter - but an anomaly, yes, that was something you could learn to live with, the thin justification you could use to paper over the ever-widening gap between you.

In all your years at school, you never copied the answers from the back of the book, not once - it's not in your nature to cheat. You don't smart against Sherlock's involvement for the same reasons that she does.

Because getting Sherlock's help on a case is like asking Albert Einstein to solve your year four math homework: a process as efficient as it is utterly demoralising. You'd get it done yourself, eventually, of course you would - but that's where the analogy falls down and shatters into a million pieces - because this isn't you puzzling over long-division, the only thing at stake the lead in your pencil and the deepening crease between your eyebrows. No: this is someone's son lying in a hotel bathroom with a bullet wound through his head, and every minute you waste is a minute extra for the killer to tiptoe further out of your reach.

There's a reason Sherlock's number is on your speed-dial. You're good at what you do.

Sherlock's better.

'Working together for a safer London', you remind yourself under your breath, as you hit dial.