Yes, this is a one-shot, believe it or not. I don't own BBC's Sherlock, but to see a more extensive disclaimer see my profile. I hope you enjoy.

Sherlock Holmes had, over the past few years, explored much of the building that the Scotland Yard called home. There were many different rooms, for many different purposes, and while assisting ("I solve them!") with some of the more difficult cases ("and let's face it, to those incompetent imbeciles nearly all cases are difficult"). Sherlock had been in a good ninety-two percent of the structure, and probably knew the layout better than most.

But as Sherlock found himself sitting in a stiff, metal chair in a cold, concrete room, staring at his reflection in the large glass window opposite him, he had to admit he had never, ever been in this part of the building.

But he knew exactly what its purpose was.

He turned his wrist from side to side, sneering at the silver cuff connecting him to the table, which was, by the way, bolted down to the ground. He tried not to show too much emotion. He knew someone had to be watching him. Actually, he was willing to bet that at least half of the entire Yard had stuffed themselves in that little room on the other side of the glass, craning their necks past one another in hopes of actually being able to see what was going on. Sherlock scratched his nose with his free hand. Let them watch. He wasn't doing anything too interesting at the moment, anyway.

They had dropped him off here twenty-seven minutes ago, give or take a few seconds. Four officers he had never met, and really couldn't have cared less even if he had. Just by glancing at his stubble, Sherlock knew that the first man was in an unhappy marriage and was filing for divorce, hoping to gain a fortune from his soon-to-be-ex-wife and her successful candle-making business. He knew that the second officer was asthmatic, although he had just bought a new boxer puppy; and the third officer, a woman, had a very serious caffeine addiction and had just been on vacation on the coast of Spain. The last officer was all too easy. By observing the state of his jacket, Sherlock could tell that the man was in a steep gambling debt, and was trying to pay it off by selling his action-figure collection on the internet. Sherlock found it amusing that they thought he was that dangerous, to require four ("rather pathetic") officers to move him.

Yes, he found it amusing, but he fully understood their train of thought.

He waited for quite a while longer. Back in the recesses of his mind, his hard drive, Sherlock knew that they were practicing some sort of technique. They were trying to make him "sweat it out", or something of that sort. Except that he wasn't sweating. Not even a little bit. Maybe, he would have been a bit nervous about why he was in this room ordinarily, but it was the last thing on his mind now. It was almost unimportant in the grand scheme of things, and he was too much distracted by his thoughts to actually feel even a hint of something.

The lights above him flickered slightly as if they were about to go out, but this wasn't the first time they had done so. Sherlock assumed that it was another one of their "techniques", and would have been quite annoyed of it, again, if these had been normal circumstances.

But of course, they weren't.

He tilted his head forward, his chin touching his chest, and he closed his eyes, thinking. The people observing ("how ironic, usually I'm the one doing the observing") him probably started to think he was asleep, as he stayed in that position for so long.

The click of a door opening invaded Sherlock's thoughts, and he snapped his head up and stared at the newcomer with his piercing, grey eyes, his posture becoming straight and rigid.

Out of all of the officers of the Yard, this was the one Sherlock least wanted to see at the moment. Heck, he would have even preferred Anderson. But while Sherlock was—not unhappy, that was too strong of an emotion, but something close to it—to see Lestrade enter his little concrete box, Sherlock was not surprised in the slightest.

The detective inspector refrained from making eye contact right away, instead staring at a file in his hand as he moved across the room. The door closed itself with a snick, and the screech of metal on concrete was heard as Lestrade pulled the other chair away from the table, setting the files down gently as he took a seat.

Only then did he meet Sherlock's eyes.

"I didn't want to believe it," the man said with a sigh. Sherlock carefully kept his face blank. "I really didn't want to believe it, Sherlock, but I can't deny the evidence." Lestrade paused, rubbing his temples. Sherlock deduced that he had been up for at least thirty-six hours, and hadn't left the Yard since then, although he had changed his clothes once. Throughout that entire time, he had only had coffee and a bagel with strawberry cream-cheese for sustenance. Sherlock knew that Detective Inspector Lestrade was exhausted. Anyone that even just gave him a passing glance would know that.

It was silent for a few moments, and then Lestrade regained himself and continued.

"You know, Donovan had always said this would happen. She would never give up the idea, but, in my head, I had always doubted her. You're constantly running off your mouth, constantly getting on everyone's last nerve. You're so incredibly antisocial, and seem to run by your own rules, but Sherlock, I had convinced myself that you would never go to those lengths. I believed in you, as much as I'm loath to admit it."

Another pause: Lestrade's frustration and anger leaching out into the air.

"Is there anything you want to say?" And there isn't really, because Sherlock knows exactly why he's here, and he knows exactly what Lestrade wants him to say. But he can't. He brings himself to look into the detective inspector's eyes, and sees that they are asking, no begging, for everything to be just a big misunderstanding, hoping that this all wasn't real.

But it was. What had happened, happened, it was all true, all real. And Sherlock really was in—he forced himself to come to terms with the word—interrogation. He continued to not respond.

"Sherlock, you murdered a person: a person with a family, and a life. Just…" he trailed off and squeezed his eyes tightly shut for a moment, and then exhaled deeply, his pent-up emotions clearly evident to the consulting detective, "Just tell me…why?"

And he knew that his answer wouldn't satisfy Lestrade. It would frustrate him further, perhaps even infuriate him. Some people, some of the ones that were listening from behind the glass would be shocked at the words, but he knew many would not. Despite all of these things, though, he said the words anyway, in as short and as casual of a way as he could manage it.

"Because I was bored."