A/N: The three are all the same age here, and roughly 15/16, in the sophomore year. I have no idea what actual AP Bio classes are like, let alone one at an exclusive NY boarding school for gifted students. And I was certainly too lazy to search. So forgive any and all inaccurracies, especially during the "deductions". I kept everything deliberately vague, but holla at me if you'd like to help with specifics.

Chapter One

It was a particularly grueling class of AP Biology, and Joan was sitting between Jamie and Sherlock like always. The two were getting along better nowadays, to the point where you might've been able to get them to admit they were actually friends-if only at gunpoint, but it was still a tense, fragile thing.

Sherlock and Jamie knew each other first, having known each other since middle school. He'd initially knew her as Irene at the time, however, as she'd been in the midst of a bold social experiment where she functioned under the false persona of Irene Adler, new American transfer student. The charade had been remarkably effective and convincing for a thirteen-year old. But then, she'd hardly been a typical thirteen-year old. Of course, neither had Sherlock. Eventually, he had cottoned on to her lies, but it had taken over the course of a school year and a swift friendship that had them practically attached at the hip to each other. From Sherlock's point of view, she was his first and best friend. Then, she turned out to be a lie.

Suffice to say, one year later, freshman year of high school, the two were decidedly enemies. Until Joan Watson. They'd cultivated separate friendships with her, unaware of the other in her life, until it had all come to a head in a rather messy fashion. Somehow though, it had resulted in a burgeoning partnership between Sherlock and Joan in his unofficial detective business, and what might've been the first genuine connection Jamie Moriarty ever had with anyone. Another side effect was the fact that the two former enemies now coexisted in somewhat harmonious fashion for the sake of their mutual friend. Somewhere of the course of a year or two, they might've even rediscovered something true in the wreckage of their past relationship with each other.

Regardless of this new understanding, they were both irritatingly prideful people who had a tendency to turn every little thing into a fight, so Joan had long learned it was best to place herself as a buffer between them if she wanted some semblance of peace.

Of course, even with such measures in place, neither was above talking to each other over Joan, not even during a class. Her two best friends cared very little for things like that, after all. The dark-haired girl was pretty sure they would not show up to class at all if it wasn't for her. Between them, she was the only one who had some respect for the fact that they were all students here, with a job to actually show up to classes and learn something.

Thus, as the teacher droned on, Joan dutifully wrote down every word on her notebook. Admittedly however, it was more out of habit and obligation than any genuine interest. Despite putting on her usual face as a good student, even she could admit to herself that the lesson was tedious and her attention wandered a little. They were going over a topic Joan had already managed to master, so really, she wouldn't miss too much if she'd decided to forgo her notes complete.

Much like her two seatmates were doing. To her right, Jamie had not even bothered to pretend to pay attention. The moment class had started, she'd taken out her sketchpad she always brought along with her and started working on some unfinished piece or another. As always, she was secretive of her work before it was finished. But from what little she could glimpse of it in the corner of her eye, Joan suspected it might've been another sketch of her. The thought sent a faint flutter through her, like always, and she was never quite sure how to feel about it.

Meanwhile, to her left, Sherlock had made similarly little attempt at paying attention to the lesson. He had his notebook out before him, at least, but the notes he was making had nothing to do with the class. A glance at them showed they were, unsurprisingly, on the latest "case" they'd received. It was about the theft of a fellow student's brand new laptop. The victim suspected it was his roommate but Sherlock had other ideas, saying there was more to it than met the eye when they'd first gotten word. Likely, he would have all sorts of brilliant new insights to offer her once class was over.

If he could wait that long, that was. Despite experience otherwise, Joan was hopeful. Maybe an old dog could learn some new tricks, after all. If not, well, she was feeling a little bored herself too, even if she didn't want to admit it.

The three tried their best to share all the same classes, which meant taking Advanced Placement options a lot more times than Joan was probably honestly comfortable with (mostly in Maths). The current subject was an exception, and one of the few they all shared an interest in.

That did not mean they all actually paid attention though. Indeed, if anything, they tended to pay the least attention to it, as much of the material covered knowledge they already knew. Both Sherlock and Jamie tended to study more advanced texts than even their Advanced Placement classes covered, in a variety of eclectic topics. Largely, Joan left their books alone, unless the topic interested her, as with biology, for example.

So, despite her pretensions at otherwise, Joan was just as ready as her seatmates to engage in some other endeavor than the one she actually ought to as a student in one of the finest educational establishments in the country. Thankfully, for her growing boredom, if not for their poor teacher in front, her best friends were quite willing to accommodate.

At the same time.

Of course.

"Watson!"

Joan was treated to a simultaneous whispered shout of her name from both directions that also managed to attract the attention of their teacher, Mr. Johnson. Sighing softly, she gave an apologetic look at the older man. "Sorry, sir." It was, in a way, her fault as well, after all. He was not, unfortunately, appeased.

"Mr. Holmes, Ms. Moriarty, if you wish to speak to Ms. Watson you can both do so after class, not during." Frowning at the two negligent students, he continued, "And if it's not too much trouble to ask, if you could perhaps also pay attention to the lecture?"

Joan resisted the urge to sigh again, but she did let her eyes close, pressing a finger to her temple in anticipation of the inevitable headache. Because of she knew her two best friends at all, they would likely be landing them in trouble quite soon.

"Your lecture on cellular division is hardly going to be winning you any prizes anytime soon, and with good reason." Sherlock was the first to strike, calmly dictating what he had managed to surmise. "From what I saw in Watson's notes, you've already made two erroneous examples in your overzealous attempts to cast some new revelations on your downtrodden topic."

"What-? I-" Before Mr. Johnson could manage to do more than stutter, Jamie decided to show off her own deduction skills.

"Of course, that is only because a colleague of yours has recently called into question some of your past work, isn't it? Perhaps on this exact topic in question. Hence the sudden review of an old lesson." Jamie questioned, with a shadow of a sly smirk that could've been vindictive pleasure of besting a so-called authority figure or at one-upping her favorite frenemy Sherlock in his little deductive games.

Because, of course, it was now a competition to see who could manage to derail their Biology teacher faster. In between them, Joan shook her head, wondering why she had ever thought she wanted anything other than sweet peaceful boredom.

"That's it!" With his face flushing unflatteringly, Mr. Johnson finally snapped. "Detention! All three of you. And I will be having words with the Headmaster! Again!"

This time, Joan did let out a sigh, placing her head in her palms as she bemoaned her association with the two most idiotic geniuses she'd ever met.

"Now, now, dear, no need to take out your stress on us." Jamie tutted disapprovingly. "Really, we are doing you a favor by pointing out your errors."

"Perhaps it's the strain of your failing marriage finally getting to you." Sherlock was quick to pounce on another detail, to claim victory on his impromptu competition with Moriarty. "I noticed you have finally stopped wearing your wedding ring, Mr. Johnson."

"Headmaster's office, NOW!"