"John. You realise you cannot actually keep me here?"

"Mm, I rather think I can."

John dragged a chair across the concrete floor, positioning himself in front of Sherlock's cell—close enough to keep watch, but far enough to remain out of reach.

Clearly he'd been planning this. Sherlock would be impressed with the execution, if only the premise of John's little plan hadn't been so irredeemably flawed.

Sherlock leaned into the bars, his voice a carefully composed blend of boredom and disdain as he pointed out the very obvious fact that, "This is idiotic. We both know it. You can't honestly believe yourself capable of forcibly confining me."

John offered a half-grin, dropping into his chair and picking up a newspaper—July 16th, editorial section, already a bit brown around the edges, ink smeared from three previous readers—from the cluttered desk to his right. "Seems I already have. Quite capably, if I do say so myself."

John had lost his mind. That was the only explanation—aside, of course, from a multitude of other explanations, including blackmail or psychotropic drugs or even an ill-conceived bet amongst Lestrade's officers as to exactly how far Sherlock could be pushed before he snapped and murdered the only flatmate he'd ever managed to keep for longer than a week, all of which were highly unlikely given the circumstances but couldn't be ruled out entirely without more data.

Nevertheless, there was no discernible logic behind John's actions.

Sherlock sighed. "Let me go."

"Nope."

His head tilted slightly in consideration. "...Please?"

"Not happening."

"All right, fine," Sherlock said, pacing the length of his cell. "I'll just escape then."

"Be my guest. And by the way, if you so much as touch that lock, or the hinges, or—I don't know—start digging a bloody hole to China, I can and will sedate you."

Sherlock frowned, because even as a figure of speech, "That's absurd, no one could dig a hole to China. And why China? How could that possibly be a helpful strategy right now? We're over a parking garage. Really, John. Think your metaphors through next time."

"Yes, I'll get on that right away. Now stop pacing and calm down. Everything is going to be fine."

Honestly, John was being completely unreasonable. Sherlock had done nothing to deserve this. No, really. This bizarre treatment was utterly unwarranted.

But if John insisted on having an inconveniently-timed mental breakdown in the middle of a case, well, Sherlock would just have to find a way to work around that. Improvise. Adapt or die. Or, in this instance, risk losing the most interesting case he'd had in the last three months, which was just as bad.

He checked his watch and grimaced.

"If you don't let me out right this instant, I'll...I'll never speak to you again."

"Promise?" John replied.

"Just unlock it!" Sherlock grabbed the bars—iron, solid build, at least thirty years old, clear signs of disuse, rust slowly eating away at the joints—and shook them as hard as he could.

John cringed at the awful shriek they made, so Sherlock did it again.

At John's raised eyebrow Sherlock stopped. He'd nearly overlooked John's earlier threat. It wouldn't do to lose possession of his faculties to the hazy stupor of a tranquilizer. Not when he was this close to solving the case.

He raised his hands in a peaceable gesture and took a step away from the bars.

Minutes passed in silence as Sherlock glared at John while walking around the perimeter of his tiny cell—originally a holding-cell, then converted to storage, then converted back to a holding-cell, likely for this very occasion, and was that a...yes, yes that was a decomposing rat corpse in the corner. Converted hastily, then, with little regard for hygiene or future use, furthering the hypothesis that the space was indeed intended solely as a makeshift prison to keep Sherlock from solving his most recent and pressing case.

Sherlock checked the time again and found it lacking along with his patience. If he didn't resolve this situation soon, the opportunity to catch up with the killer would have passed.

John went about reading his newspaper, completely ignoring Sherlock's distress.

If John wouldn't listen to reason, he'd just have to make an emotional appeal of some sort. What emotion would be appropriate for this situation? Anger was likely counterproductive. Humour? No, that was stupid. Sympathy, perhaps? John did tend to be the sympathetic type.

"John?"

"Mmhmm?"

Sherlock cleared his throat and drooped his shoulders. "I don't feel very well. I think I've come down with something."

"No you haven't."

Damn.

Sherlock put a hand to his forehead. "I have a fever."

"No you don't."

He was running out of options. Surely John would take pity on him if the matter was serious enough. Sherlock clutched at his chest, reporting in a panicked voice, "I think the stress of confinement may be inciting a harmful cardiovascular response almost certain to lead to my untimely death."

He paused, watching closely for John's reaction—or lack-thereof.

"Did you know they're debating whether to increase the fare for the tube again? It's like it never ends."

The man was oblivious to his suffering. "I'll die if you keep me here," Sherlock said.

John continued on, "I mean, where does it stop? At this rate it might be a better investment to get a car. Can you imagine that? You'd think they'd want to encourage the use of public transportation."

Insufferable. John was simply insufferable.

"I'll buy you a car if you open this door right now."

"Wasn't my point, but thanks for the offer."

"I'll hold my breath until I pass out," Sherlock threatened.

John chuckled.

"I can do it, too," he said. "Just ask Mycroft. He once stole my dessert and I ended up with a concussion after blacking-out and bashing my head into a chess-table. He was grounded for a week."

"Sit down and relax, will you?" John turned the page, shaking out the paper. "This is for your own good."

"My own good?" Sherlock scoffed. "I hardly need you to determine what is and is not for my own good."

"Right. Because you're so adept at taking care of yourself. You'd starve to death if I didn't do the shop every week."

Sherlock huffed. "It's not as though I'm about to rush off and blunder into their trap—I most assuredly am not an idiot. I can handle this case just fine, regardless of the suspect's interest in dismembering me. We've been through worse before, haven't we? Why must you impede my investigation now, of all times? I'm so close, John."

John finally looked up from his reading, his eyes serious and his jaw set in that way it got when Sherlock left the milk out to spoil too many days in a row—seven, consequently, was John's limit. "Because, Sherlock, as infuriating as you are, I still prefer you without your head blown off. All right?"

Was that what this madness was all about—the integrity of his skull? "Oh please. That was obviously an idle threat. They don't have the resources."

"Lestrade thinks they do," John countered, as though what Lestrade thought had any bearing whatsoever on reality. "And after that fiasco in the park, I'm inclined to agree."

"Don't you see, John? This could be my only chance to find out how deep this goes! The evidence will be long gone by the time Lestrade gets there, and so will all of their operatives."

John's focus returned to his paper. "Lestrade will handle it. You'll have to let it go, just this once, and as soon as you're out of the line of fire, you can go back to chasing down as many corrupt politicians as you want."

This had gone on long enough. What little patience Sherlock had possessed plummeted and he informed John in no uncertain terms that, "I don't need you to take care of me. I don't need anyone. The only thing I need right now is to get out of this bloody cell, and if you won't help me then you are utterly useless to me. Useless, John. If this ridiculous performance of yours causes me to lose this case, I...I'll never forgive you."

John stilled for a moment, then glanced up at Sherlock—irises darkened, slight squint, furrowed brow, pursed lips—and nodded sharply before returning his attention to the news, worrying the edge of the paper between his thumb and index finger.

Unexpectedly, Sherlock suddenly didn't feel so well, which didn't make sense since he'd felt fine all day and he hadn't eaten anything that would disagree with him—well, he hadn't eaten anything, in fact, and that had never troubled him before. How odd. It was...uncomfortable.

He went and sat on the metal frame that once held a mattress, and wondered idly about the likelihood of it collapsing under his weight—almost inevitable, but he continued sitting there anyway. It wasn't resignation, and he certainly didn't concede because John told him to. He was biding his time and, well, there wasn't really anywhere else to sit but on the floor and he'd just had his coat dry-cleaned. That's all.

Sherlock dusted off his slacks. His body continued to annoyingly alert him to what seemed to be mild intestinal difficulties.

He was considering the possible causes of said difficulties when it occurred to him that the last time he'd felt this strange was when he'd been recovering from the influence of an accidentally inhaled mind-altering substance. He had said something rather regrettable that led to John not talking to him for nine hours and thirteen minutes until Sherlock apologized and...oh. Oh, of course. Obvious.

Sherlock stood up quickly and moved toward John. "John, I didn't mean..."

"Look," John started, rising to join Sherlock at the bars. "I'll let you out as soon as Lestrade gives us the okay. I promise. I just can't trust you right now to not get yourself killed. This morning you risked getting skewered—"

"That was a calculated risk," Sherlock clarified.

"—just to get to a bloody piece of paper on a park bench."

"That paper could have been integral evidence, John."

"It was a piece of paper, Sherlock."

"Well how was I to know that without looking at it?"

"That's never stopped you before, and it sure as hell isn't an acceptable excuse for that kind of recklessness," John said, his chin tilted up defiantly as he pressed closer to the bars.

Sherlock, too, had found himself rather close to the bars in an instinctive attempt to use his height to assert dominance—which obviously wasn't working because this was John. The man was impervious to intimidation.

"Yes. Well. I can see we've reached an impasse," Sherlock said. "Let's go discuss the matter further over tea like civilized adults, shall we?"

John frowned. "I'm still not going to let you out. You have no sense of self-preservation at all."

"Of course I don't," Sherlock agreed. "I've got you for all that."

A faint pink hue dusted John's cheeks as he shifted in what was probably an attempt to create distance—73% likelihood—but Sherlock wrapped his hand around John's wrist to keep him still. John didn't try to pull away.

Sherlock was aware of everything at once: the irregular pattern of John's breath, the heat radiating from him through the bars, the coffee—black, no sugar—on his breath, dilated pupils, slightly parted lips, proximity, proximity, proximity. He wondered if his own pupils were dilated.

John smelled like smoldering oak trees, a souvenir from the blaze earlier in the day, and all right, perhaps Sherlock could have been a little less reckless.

"I don't have the key on me, you know," John said, his voice hushed and uncertain.

"I know," Sherlock told him, tongue brushing across chapped lips.

John's eyes followed the movement. "You can't trick me into letting you leave."

Proximity. Hmm. Intriguing, the responses in oneself and others that could be provoked by something so simple as the possibility of contact.

"I know."

"I'm serious, Sherlock. I won't let you out. Not until it's safe."

He'd have to experiment further; test conditions, determine boundaries, identify variables.

"I know you won't."

"Then let go of me."

"No," Sherlock decided, because that would almost certainly interrupt the strange pull of an unidentified gravitational force that seemed to draw John closer, and he hadn't yet constructed an adequate equation with which to describe it. Was there an innate threshold that triggered such a response, or was it dependant on individual factors? Did they, as variables themselves, share the same qualities in equal proportion, or was balance even more volatile than it seemed?

"Sherlock..." Closer. John sucked in a quick breath, and Sherlock could feel the displaced air stir against his skin.

Remarkable.

The intrusive ring of John's mobile derailed Sherlock's thoughts like a body strapped to train tracks.

John pulled away abruptly, clearing his throat as he answered his phone, "Well? Oh thank god. I'll let him know."

"Lestrade," Sherlock deduced, because obviously it was Lestrade, but he'd never pass up an opportunity to impress his flatmate, no matter how small.

"Yep. It, uh, looks like he managed without you."

Sherlock's eyes widened slightly. "You mean he actually apprehended the suspect?" Unlikely. Not strictly impossible, but unlikely.

"You don't have to sound so surprised. Here," John said, digging the not-so-cleverly-hidden key out of the desk drawer, then unlocking Sherlock's cell, all while avoiding direct eye contact. "You're free."

He was, actually. Quite free, in fact. With the suspect in police custody, Sherlock wouldn't get access to him for a while. No need to hurry. And the key to a good experiment was repeatability, after all. Since John had divested Sherlock of his afternoon activities, it was only fair he should be responsible for replacing them.

When the door swung open, Sherlock tugged John in and closed it behind them, pressing him against the bars.

John gasped.

Fascinating.