A/N: Kudos to eagle-eyed alix33 for catching a plural possessive mistake way back in Chapter 1, a skipped word in Chapter 4 (I'd fixed it on Ao3, but not here), a bad apostrophe and hyphen in Chapter 5, and another plural possessive flub in Ch 8! Also, both "Apparation" and "Apparition" are used in the books - though the latter is used more than the former, I've decided to stick with "Apparation", to keep it more distinct from the common word, and to maintain form agreement with the verb (as in, say, exculpate/exculpation).

Edit: Thanks to \u\monstrousbird, for catching the cages\cases mistake I swear I fixed...stupid Memory Charms...

Edit 2: More thanks to somnolentSlumber, for noticing an extra comma, and the appropriate style for book titles, which I also could've sworn I looked up early on, but apparently not!

Edit 3: Thanks to JoseHood for remembering (and much chagrin on my part) that I sent Parvati to Hufflepuff this time!

o-o-o-o-o

The thing was, it was all well and good to want to be creative, but she was still limited by the actual resources at hand. She didn't have any spells that were suited for an adult duel except perhaps the Disarming Charm, but unless one led with that against an unaware target, it was the height of optimism to expect to catch a trained opponent without a Shield that would easily block it. The few jinxes she knew wouldn't touch a Shield, and though she had a couple ideas for working around that, they were stop-gap measures at best. So despite her determination, as she roamed the halls of the castle, Hermione second- and third- and Nth-guessed herself.

She'd sort-of tried to tell a single authority figure, and when that hadn't immediately worked, she'd given up. And as her adrenaline faded, she began to consider the possibility that her current sense of urgency might be based more on her own guilt and contrariness towards her older self's abdication of responsibility, than on the genuine strength of any arguments for avoiding delay.

Accordingly, she'd thought of a way she might refine her own plans while simultaneously at least exploring the possibility that telling a Professor might go better than she imagined. She could get some tactical advice - couched in theoretical questions, obviously - while sounding them out a little. But the questions she needed to ask didn't seem quite natural enough for her ideal choices of confidant, Professor Flitwick, or Professor McGonagall, and she thought they'd be too likely to rouse suspicions.

But there was a Professor whose job it was to answer these sorts of questions, who seemed rather distractible in any case, and unlike the other two - as luck would have it - whose posted schedule suggested he had a free period at the moment.

When she arrived at his office, however, she hesitated before knocking, as it sounded like he was already meeting with someone - fragments of conversation were drifting into the corridor through the closed door.

"...can't...significant...imagine him...good excuse. ...perfect distraction...the bat has stopped...occupies them..." After a pause, Professor Quirrell's voice continued. "...as you wish. ...only meant...yes...know I am."

While Hermione automatically tried to puzzle out the meaning of what she was hearing, she also stepped away from the door, since eavesdropping wasn't acceptable behaviour - for a moment she thought darkly of Mr. Odious, then remembered he hadn't been eavesdropping, and that had really been her own fault. In any case, she didn't have quite enough context to form any good theories about what the Professor was talking about. Though it was rather curious that none of what she was hearing was stuttered. That might just be selection bias, though...actual stammers tended to be more quiet than the completed words surrounding them, so it could be that only the latter were making their way past the door? Or perhaps his issue was only with public speaking, and he was just more comfortable with whoever he was meeting with than speaking in front of a large class?

When she realized that she hadn't heard anything at all for some time, but no one had come out either, she stepped forward and knocked on the door.

"Professor Quirrell?" Hermione asked, hesitantly. The door opened, and Hermione nearly choked on the wave of garlic scent that surrounded her before she even saw the Defence Professor, who was actively adjusting his turban.

"Ah, M-m-miss Granger, how m-m-may I help you?" Hermione did not entirely succeed in resisting the urge to lean slightly to look behind him, but she didn't see anything regardless.

"I had wanted to ask a few questions about Defence, but if you're busy…"

"Oh, n-n-not at all, p-p-please come in," he said, standing aside so she could enter the office past him. He closed the door behind her.

There were a few small bookshelves, as well as a larger set of shelves with a collection of curious items, some of which were cages or glass cases containing small magical pests. Hermione sat in one of the two ordinary chairs in front of the desk, though her brow furrowed as she did so.

There was no sign of anyone else in the room, nor of another door by which the Professor's guest might have departed.

Hermione knew for certain whoever he'd been speaking to hadn't Disapparated away, as Hogwarts was permanently bewitched to prevent Apparation or Disapparation anywhere on the grounds - that was mentioned more than once in Hogwarts, a History. He might have been speaking to a portrait, but there were none on the walls - which was interesting in itself, as nearly every other vertical surface in the castle seemed to hold at least one portrait.

She'd read about the Wizarding Wireless, though she'd understood it to be strictly a broadcast phenomenon, and not used for person-to-person communication...magical society seemed very attached to owls and letters. There'd been references to a "Floo Network" which was used for travel or occasionally used more like a telephone - the mechanics of how that worked Hermione was a bit uneasy about - but there was no sign of a fireplace either...perhaps it had just been some specifically enchanted item she hadn't yet encountered.

Meanwhile, Professor Quirrell had taken the chair behind the desk and now cleared his throat expectantly.

"Oh, yes," said Hermione, suddenly remembering why she'd come. "Well, while I do appreciate your having added some more 'practical' Defence to our curriculum - however unfair it might have been for you to have been pressured so - it's still more...recovery, than defence per se? Undoing things is all well and good, but if the person is still there, doing more things to you…" The Professor looked irritated for a moment, then thoughtful.

"Ah...yes. Someone hit you w-w-with a spell even...I have n-n-not encountered, some v-v-variant on the S-s-seer's Hex, and you are understandably c-c-concerned about a repeat performance. What d-d-did you see, if I m-m-may ask?" Hermione immediately dropped her gaze to her lap.

"Torture, death. I'd rather not talk about it, if that's all right?" she said, quietly. Which was true, but she was also being mindful of the warning she'd received about Legilimency, or otherwise revealing the details.

"Oh, of c-course, my ap-p-pologies," said the Professor, though to Hermione's mind he still sounded more curious than sorry.

"So...if I find myself outmatched, and I can't just run, what are my options? There must be something?"

"In general, I would s-s-say you can only s-s-seek to increase your p-p-power. Those with power can always imp-p-pose their will on those with less, or without...it is the w-w-way of the world." He sounded mildly wistful about this bit of philosophy, but not as disappointed about it as Hermione would've hoped a Professor might.

"Professor, I'm not even twelve yet. I'm doing my best to learn all the spells I can cast - I've tried nearly four dozen now, including most of the Grade 2 spells" - his eyebrows raised slightly - "but a Shield Charm is even trickier, and apparently requires some magical analogue to strength, as do the spells that might break a Shield, and everything I've read says that requires not just practice but simply age." She looked back up at him, her expression showing the genuine frustration she felt.

"Hmm. A d-d-dilemma indeed." He thought for a moment. "There is s-s-strength in numbers, of course, though s-s-some might say r-r-relying too much on others is ill adv-v-vised." Hermione shook her head.

"If, er, someone's got it out for me, I'd rather not put anyone else in harm's way." Professor Quirrell shook his head.

"Very n-n-noble, if not as l-l-logical as I might expect from a R-r-ravenclaw," he remarked, and now there was disappointment in his voice, cutting deeply where Hermione was most vulnerable. "You c-c-could borrow power from elsewhere, p-p-pre-enchanted items and s-s-such, though they merely exchange one s-s-sort of power - galleons - for another, and these t-t-too are unwise to r-r-rely upon…"

"That's a good idea, and I'll look into it, but owl-order takes time, and I-...I'm vulnerable now." The Professor nodded, tapping at his desk thoughtfully.

"T-t-tell me...do you know, or s-s-suspect, y-y-your enemy's identity?" Hermione dropped her eyes again. This was the opening she'd been watching for, and the way he'd asked…

"I...even if I did, considering the Hex, would anything I said be believed?"

"Ah? P-p-perhaps you have a p-p-point, though I think y-y-you may underestimate the p-p-propensity of a certain s-s-sort of self-righteous p-p-person to credit even improbable accusations made by y-y-young girls. S-s-surely you have read of the S-s-salem Witch Trials?" Hermione blinked at this. She had, of course, though aside from a brief mention in A History of Magic (which perhaps would have been better titled "A Limited History of Magic with a Particularly Narrow Focus on Europe, Particularly the British Isles"), she hadn't yet looked deeply into the events from the perspective of magical society. "But that is n-n-not what I meant," the Professor continued. "If y-y-you know your enemy, you m-m-may tailor your approach...use subtlety, deception, surprise...do not w-w-wait to be attacked, strike first, come at him in a w-w-way he will not exp-p-pect. Or...lay a t-t-trap he cannot resist." His voice became cautious and quiet, his eyes uncertain. "Historically, it is how m-m-most truly powerful Dark Wizards have b-b-been defeated...even temporarily."

Now Hermione openly stared. It almost sounded like he was egging her on, which was not at all how Hermione imagined a Responsible Adult acting, and she felt an underlying sense of unease at the turn the conversation had taken. But then again, she had asked, and she'd said herself that thinking about this sort of thing was his job, and talking about powerful Dark Wizards having been defeated was oddly comforting, as it put her own problems in perspective. She was sorely tempted to just tell him her suspicions, add in all of the circumstantial evidence she could reveal, and hope for the best. Some of what he'd mentioned - surprise, for one - she'd already thought of, but a trap was definitely a good idea. He'd sounded a lot more capable during this conversation than he had in any of the classes they'd shared so far, and despite his speech impediment, his spellcasting did seem quite good. And she would feel much more comfortable confronting a possible murderer with a trained adult wizard present.

But after a moment's thought, Hermione decided not to bring up her theory with him directly. Yes, her older self's concerns were still suspect, but in this case they aligned with her own uneasiness about the conversation. Still, the nervous man did seem somewhat pitiable, and she couldn't suppress an urge to try to cheer him up.

"All right, then. I think you've given me plenty of things to think about, and I'm sure they'll be helpful. I really appreciate you taking the time, thank you."

"Of c-c-course, Miss Granger. And w-w-we've only had one week of classes, r-r-remember...I think, when all is s-s-said and done, this school year w-w-will be seen as having been more than adequately instructive."

He smiled broadly.

o-o-o

The portrait of the large woman - her name was Gloria, and while Hermione had heard even Professors refer to her in a blatantly insensitive way, she refused to do so herself, since portraits were clearly sentient if not sapient - which guarded the Gryffindor common room had informed Hermione upon being asked that Ron (and Harry) had gone off some time ago, and further inquiry had revealed that she had overheard them say something about tea with Hagrid. Hermione had considered going off after them, but she needed to handle things delicately at first, lest she lose the element of surprise.

So instead, despite her fading sense of urgency, she decided to just wait by the portrait for Ron to return. She would've liked to practice some spells in the interim, but using magic in the corridors was against the rules - if poorly enforced - and there were no classrooms near enough by for her to be sure of not missing the boys returning. Instead, she just reviewed some of her basic spell experimentation notes (partially in an attempt to distract herself from her increasing nervousness and guilt).

She'd discovered that certain spells "stacked" - to wit, multiple Levitation Charms would require less effort to lift the same thing, or allow a heavier thing to be lifted with the same effort - though since the spell was actively sustained that of course required multiple casters, unless one could somehow contrive to cast from a wand in each hand, but it wasn't clear if that might not just halve the efficiency of each spell. She had tried using the Engorgement Charm on something multiple times, though, and it would grow larger each time by the same proportion. By measuring with a good metric ruler she'd estimated that proportion to about 78.5%, which was close enough to Pi/4 to make her suspect that might be the exact ratio, and seemed like an intriguing clue about the internal workings of magic.

Other spells, however, like the Impervius Charm, or the Floating Charm, didn't seem to multiply their effects with repeated castings, but instead simply retained the strongest individual effort they'd been cast with. Hermione wondered if that was due to elements of the spell's construction, or more a factor of certain specific spell effects being more or less conducive to reinforcement, but she hadn't tried enough spells to have noticed any obvious patterns yet. She had discovered that the Floating Charm, like the Levitation Charm, did require at least a minor level of sustained concentration, it just didn't need the constant wand attention the latter did. But accordingly, it couldn't be directed beyond the initial casting, all things did was float at a height proportional to the strength of the Charm and inversely proportional to their weight. Which in turn suggested that the spell wasn't blocking gravity or mass - then height ought to be largely irrelevant - but rather creating a field of force in a specific relationship between the item and the floor (because putting something else underneath a floating object didn't make it any lighter, or interfere with the original object). That much seemed borne out by her original test of it on her trunks, but she'd have to check the edge cases, see if it was really relative to the floor, or "ground level", or the nearest solid surface below the object at the time of casting.

Even as she re-read her notes and jotted down further observations, sitting against the corridor wall, she couldn't quite keep her mind occupied enough to avoid further self-recriminations. Yes, her theory might seem insane to someone's objective judgement, but surely the matter was serious enough that - presented directly with the rat and a sincere accusation - a Professor would extend the benefit of the doubt long enough to at least test it?

But despite Professor McGonagall's counter-example, it was all too easy to imagine being marginalized, ignored, dismissed. Even in the case of the Transfiguration Professor - who seemed unusually fair-minded - she hadn't actually reconsidered her own opinions until presented with strong evidence of Hermione's claims. So more than just securing the murderer, she really needed something firm enough to demand attention.

o-o-o

After quite a while of waiting and review, the outline of a plan began to gel in her mind. She'd need to test a couple of spell interactions, and borrow something she'd seen from one of the older Ravenclaws... She even thought she could make the scheme relatively safe...but there was an unavoidable element of risk in actively baiting someone who had already killed once to preserve his secret. She'd work out the details, but she'd continue to consider alternatives.

As was her occasional habit when doing some creative thinking, and since Ron and Harry still weren't back yet - how long could it take boys to finish having tea, anyway? - Hermione pulled a book from her bag that she'd already learned by heart. Somehow the act of re-reading often helped occupy her more linear thoughts while subconscious associative processes continued in the background until they had come up with something useful to report.

It was Hogwarts, a History, of course...the book that, in her early reading weeks ago, had given her the most inspiration, the most optimism, the most wonder about what her life might become - even in the face of some of the other books which had covered less rosy topics. She sighed a bit wistfully about how drastically her life had changed, and how it was still an open question of whether or not that would turn out to have actually been a good thing.

Hermione opened the book to a random page in the middle, and-

It was blank.

She turned the page, and the next two were blank as well. Baffled, Hermione riffled through all the pages. For a moment, it seemed the entire book was blank - and now examining it closely, it seemed a lot shabbier than she remembered it being, the binding was all cracked and even some of the pages were a bit loose...had someone switched her copy out as a prank? But no...in respectfully tiny script at the bottom of the inside cover, there was the line, "Property of Hermione Granger", just as she'd written it…

Just as she'd written it…

'When she first bought it in Diagon Alley' was the logical continuation to that thought, it was the first thing she did with any book she bought. Even if it seemed a little wrong to deface a published book in any way, Hermione never intended to part with a single book she'd purchased, and putting down her name was a small gesture towards affirming that commitment, even if only to herself. Plus, it had discouraged other students from messing with her books.

It was the logical answer, but all the same, she couldn't remember having done it. She'd read the book, of course, she knew it by heart, so it must have had properly printed pages at one time. But the actual "ritual" itself, running her finger down the spine, around the edge, to lift the cover, write her name, and make the book hers…

The obvious explanation presented itself, and she felt a low growl rising in her throat.

"I swear...by whatever God or Powers may or may not be listening or indeed exist, if I do one thing, I will find a way to defend against, undo and outlaw these awful, thrice-cursed, reprehensible, ought-to-be-Unforgivable Memory Charms!"

She'd only just begun to build up a proper outrage - helped by some pedantic part of her noting that had really been three things, not one - when two heads poked around the corner of the corridor. They wore cautious expressions, which mostly relaxed when they saw Hermione.

"Blimey, Hermione," Ron started as they came around the corner and approached her, "we thought we heard...well, we couldn't make out the words, but it sounded like somebody getting leaned on hard by a Sly-"

"It sounded like you were upset," Harry interrupted, elbowing Ron, who looked at him, baffled. "Are you alright?"

"For your information," Hermione began, getting to her feet and letting the mystery of the book drop, both literally and figuratively, "I was only stating my determination to do something about one of the great many things that seem to be conspiring of late to send me utterly 'round the bend!" The boys each took an involuntary step away from her, but Hermione stepped even closer to Ron, her finger rising in admonishment. "And if that makes me 'sound like a Slytherin', I suppose that's just another piece of evidence that what they have to deal with may be driving them completely out of their minds as well!" The boy held his hands up defensively.

"I'm sorry! I just meant, you sounded scary, that's all...I'd never call someone a Slytherin, that'd just be…" he trailed off, apparently at a loss to describe the level of offence such an insult would constitute. Hermione stared, struck speechless at how vastly he'd apparently missed the point. Was he doing it deliberately? Surely no one could be that consistently-

"Is it something we can help with?" asked Harry, mercifully interrupting her thoughts. Hermione took a few deep breaths to calm herself.

"No, I don't think so, but if I think of anything later I'll let you know. Though there is something else I'd wanted your help with. Both of you," she amended, trying to keep her tone positive as she reminded herself that she really did need Ron's help, and that her plan might pose a slight risk to his life - if less so than her own, and not much more than he had sharing a dorm with Scabbers anyway.

"Is it broomstick flying?" asked Ron. "I know Flying class starts next week, and I've only had a little practice at home but I guess muggle-borns don't get any, so I'm sure I could give…" He trailed off, looking concerned, and Hermione quickly smoothed away whatever expression on her face must have produced his reaction.

"No, it's not Flying," Hermione said, calmly. "Though I appreciate the spirit of the offer. It's a matter...", she paused, then lowered her voice. "Well, it's really important, and maybe a bit dangerous, but I shouldn't talk about it in the open..." Hermione was gratified to see that this statement - which she'd taken some care to craft specifically to appeal to most boys' flighty romantic notions of adventure - had the intended effect. Their eyes widened and they instinctively leaned in closer.

"Is it whoever hexed you?" Harry whispered. "I've noticed a few things, and I know how it sounds, but I think there might be something going on with" - Hermione's eyes widened...had Harry actually come to the same place she had, by some other route? - "Professor Snape," he finished, portentously. Her eyes became less wide, but more confused. But she did not correct him, instead putting a finger to her lips and looking around meaningfully. Harry nodded apologetically. "An empty classroom?" Hermione shook her head.

"Someone else might walk in just as easily as we could, or listen at the door."

"We could go up to our room," Ron suggested, his own tone conspiratorial. "If anyone else's in there, I'll send 'em straight off, and if anyone does show up, at least they're a Gryffindor and you know you can trust 'em."

"That could work," Hermione agreed, nodding. Step one accomplished - get invited to their room without mentioning it at all. Throughout every stage she had to try to make sure she gave no sign of specific interest in Ron's pet, lest he catch wind of it even second-hand, become suspicious, and possibly act before she was ready. She might have brought Ron and Harry into her confidence, but even if she could trust them not to let anything slip, she was nearly certain they would not then cooperate with the later stage of the plan where they were safe and she put herself in the most danger.

Hermione collected her things from the floor, and they duly escorted her up into Gryffindor tower - she was not particularly impressed with the password, but at least it was Latin - and Ron actually seemed a little disappointed that their room was empty when they arrived, and he would thus be unable to demand someone leave. Empty of people, at any rate - she did her best to avoid staring at the rat while not looking like she was avoiding staring, but the possible-murderer was sleeping on Ron's bed,and it was really all she could do to avoid commenting. Then again, would it be out of character for her not to comment on a rat sleeping on someone's bed?

She avoided the issue by turning her back to him deliberately. This also allowed her to shift her bag so her body shielded it from his view, and put her hand inside to grasp - but not withdraw - her wand. This was really the riskiest part, since she had to set out the bait, and he might panic, acting immediately instead of waiting for a better opportunity. Accordingly, Hermione watched Ron and Harry's faces closely - if there was any indication in their expressions that the rat on the bed behind her had suddenly become an adult wizard, she would dive to the floor while casting an Amplifying Charm at her own throat, then scream loudly and continuously for help, mentioning "Scabbers", "Animagus" and "P.P." specifically. In her judgement, without significant advance preparations, she had no chance in a duel against a trained wizard - particularly one without apparent moral compunctions - her best hope there would be that he would realize he didn't have time for Memory Charms or vengeance and would simply try to escape as quickly as possible. Just in case he did get off a Memory Charm, she'd also made a note about this plan and stuck it into one of the books she'd been reading. She took a deep breath.

"So. I don't have any evidence yet of who is responsible - though I think I know how we might get some - but I believe Madam Pomfrey's death was no accident." There was a soft sound behind her, and though the boys' eyes did widen, their gazes didn't shift - her guess was that the rat had startled. "People who know her well just don't think she'd ever make a mistake like that."

"I dunno," said Ron, "Dumbledore himself said so…"

"He's also sealed the castle, you know - surely you've heard Lavender complaining about it? I think he must, like me, suspect. But I have an advantage he doesn't…" Their considering looks confirmed they had been treated to Lavender's conspiracy theories about her wand, but at her last assertion, they showed renewed skepticism.

"Come off it...I mean, you're great and all, for a first-year, but this is Dumbledore we're talking about...what can you do that he can't?" objected Ron. Hermione did her best to ignore the qualified compliment and continued laying the trap.

"Science," she said. "How muggles figure out how to do all sorts of surprising things without magic. Specifically, I know things about how living things are put together...some of which must be constant, even under Disillusionment or Transfiguration...and the fact that we leave tiny bits of ourselves everywhere we go. If there was a murderer, he or she was well-hidden, but unless they used very specific cleaning Charms, those traces should still be there, even days later...and we could track them all the way to wherever the culprit is hiding." Hermione felt fairly bad about this part, since it was more than half made up - she had no idea if any genetic material stayed invariant under Transfiguration, among other things - but she resolved to straighten them out on the accurate science later. The most important part was that it sounded plausible to her quarry.

"You're talking about DNA?" Harry asked, while Ron looked between them, blankly. Hermione nodded. "I guess that could work," he said. "But wouldn't you need computers and machines and stuff that don't work at Hogwarts?"

"That's where magic comes in, and a bit of the danger. There's something called a Supersensory Charm, that can let you greatly improve or expand one of your senses, like see in all directions at once, or smell something burning in the oven from a neighbor's house a mile away. I think if I cast the spell just right, I could actually smell the specific traces - though I'd need to be in the room alone at first, so it wasn't confusing with too many active sources - I'd need you two to get Madam Wainscott out of the Hospital Wing." This bit was also partially invention - there was a charm like that in Practical Household Magic, but Hermione would be rather surprised if it allowed the level of detailed discrimination she was describing. The part about needing to be alone was purely to provide an enticing scenario for the murderer to capture her, question her about DNA evidence and removal of the same, and then presumably Memory Charm her. It would be a risk for him, but not as risky as the murder itself.

"Huh," said Ron. "I guess, I know mum's used that spell before. And I'm sure we can get the nurse away, we'll just have to get one of us hurt somewhere close - but not too close - and then get her to come running. That's not too dangerous though, since we're actually trying to get a healer there, only not too quickly?"

"Ah...that's not exactly what I was thinking, but I suppose," said Hermione cautiously. "But what I meant about the danger is that I did a bunch of reading, and if the Supersensory Charm is cast too strongly and you're not used to that level of sensation - and no human could be, really - it can produce odd effects...confusion, memory loss. That would be true for any person, but it's my plan, so I'm not going to let someone else to take that risk." Entirely made up, that bit, but it sounded plausible enough, she hoped. Hermione couldn't help holding her breath, this was the key moment...if she was forced to be more explicit, it could raise suspicions. A gift-wrapped excuse for Hermione to have memory loss, plus one additional crucial opening...she heard more scrabbling behind her as the rat actually tried to attract attention to itself, it all depended on Ron and Harry now.

"No offense, but I would've expected you to go straight to a Professor," said Harry, and Hermione cringed inwardly.

"I didn't think any of them would believe it. The science is pretty new, even to muggles," she replied quickly, with two separate truths that lied by implication.

"It's probably for the best anyway," said Harry, "what if it was a Professor…" Hermione really wanted to talk to Harry about where he'd gotten the notion that Professor Snape was 'up to something' - let alone murder - but her attention was all on Ron, who was moving past her in response to his rat's agitation. His face seemed thoughtful. Come on, Ronald, prove me wrong about you! Please, she thought fiercely, as if she could will the idea into his brain.

"Hey," said Ron, suddenly. "You said no human, but what about Scabbers? He has a pretty good nose - he's always able to sniff out sweets and such...do you think that Charm might be safer on him? Even if he's not used to it enough, I'm not sure he'd really notice if he had confusion or memory loss, he sleeps so much." Hermione spun towards him and her elation - that he'd voiced the idea both she and the murderer had needed him to - was sufficient that she didn't even have to try to fake surprised enthusiasm.

"Ronald, you're brilliant! Of course a rat's nose would be so much better to start with, it's probably perfectly safe for him...and if he doesn't smell anything, there's nothing there to smell." And that was step two - Scabbers had invited himself along, and she'd planted various options he could feel confident about...just accepting the spell and pretending not to smell anything, or taking advantage of Hermione being alone with him to do something more active about her suspicions - not that she intended to give him much chance to get away with either. Ron was beaming, and she couldn't tell if she was imagining that the rat now in his hands looked pleased with itself as well. "I have to fetch a couple of things, meet me outside Gryffindor tower in, say...half an hour? We can do everything while almost everyone is in the Great Hall starting dinner."

She rushed down the stairs before they could say anything, then out of the common room, sprinting towards Ravenclaw Tower. She just needed to borrow a key item from an upper-year housemate, test the spells involved in her plan, and get back to Gryffindor Tower in less than thirty minutes. If the tests didn't work, she could always fall back on contriving for a Professor to show up at the appointed meeting time, and when they did, insisting they test Scabbers on the spot. Professor McGonagall would probably be best in that case, but if it came to that, she'd take whoever she could get.