Author's note: Another AU, another multi-chapter (who is happy? Noone? Well, I am!) and this time, it's Sherlock's turn. Though I couldn't really run him into a psychopath, like I did with John, because – well, the show told us what he'd be like, didn't it?

So my brain decided to write this, though I have no idea how, and I have no plan how long this is going to be – than again, as my many faithful readers (sarcasm) know, I very rarely have a plan when I start writing.

Warnings: Drug use/addiction, crime, quite a lot of angst, I'm afraid.

I don't own anything, and please review.

He doesn't remember how he got here. Or where here is, exactly.

All he knows is that, suddenly, he wakes up on a cold floor, in what appears to be a quite dark and cold building, freezing, exhausted, disoriented.

That's the first thing he notices. Or rather the second, because the first thing he realizes is that his skin crawls and itches. All over his body.

He's confused, and that's not a feeling he's used to, nor is it one, he decides, that he particularly likes.

Where is he? What happened? Why is he here? And where is John?

John... The thought of his flatmate brings back a memory, at least.

There had been a case... Lestrade had called. Sir Eustace Brackenstall, a MP, had been found dead in his London house, while his wife, Lady Brackenstall, was discovered unconscious and tied to a chair next to the body. Once she'd regained consciousness, she had made a statement and accused a gang of three robbers – the Randalls.

Sherlock had known about them for a while now, as had the police. They had first come to his attention when they had begun, about a year ago, to rob people walking home late at night.
Lestrade had finally consulted him, because even the police had to admit now and then that an officer in plain clothes working undercover and trying to find out in certain pawn shops known for dealing with the underworld if some of the goods had been sold still sticks out like a sore thumb, no matter how good his act might happen to be.

Sherlock's homeless network, on the other hand, belonged in the street, was part of the cruel and hard world the robbers inhabited, and therefore, it had taken them less than two weeks to find out their names.

As it had turned out, they were a family; a father and his two adult sons. Even Sherlock had had to admit that a whole family turning to crime was a rather interesting concept; his sole complaint was that the crimes themselves should be so uninteresting.

Lestrade, as he usually did, had ignored this comment and started a country-wide search for the gang, because, there they had agreed, it was only a matter of time before they stopped robbing and turned to breaking and entering, which usually brought much more money. And, since some of their victims had landed in hospital, even though they hadn't even tried to resist –

It was only a matter of time before someone was gravely injured or worse.

That seemed to have happened, but Lestrade had a "funny feeling" about it, as he put it. It wasn't the lack of physical evidence: They only knew what the robbers looked like because one victim had seen a reflection of them in a shop window before a hand had clasped over his eyes and mouth, but there had never been DNA or any other clue, really: they were too smart for that. No, it was a hunch of Lestrade's, and Sherlock, though he'd never admit it, wanted to help his friend.

The friend who'd let him sleep on his sofa when John had kicked him out after he revealed himself to be alive. He hadn't even been that shocked to see Sherlock: his only comment had been "Took your time, didn't you? So give him some, too. He'll come around." He'd been right, and Sherlock and John were back at 221B, solving crimes and bickering like in the old days.

Though John knew nothing about Sherlock's nightmares, or the room in his mind palace where he kept the memories of the years spent in hiding and bringing down Moriarty's web chained, because they had the annoying habit of creeping out and throwing themselves over him.

But nothing of that was important when he had a case.

So he'd simply told Lestrade he'd be there soon, called out to John, who'd of course by this time already laid aside the book he'd been reading, and they'd left the flat, calling out to Mrs. Hudson on the way.

And then...

Sherlock winced as his temple began to throb. Great, now he had a headache too.

And the last thing he remembered was leaving the flat with John. He didn't even know if they'd made it to the crime scene.

He'd just woken up somewhere he had no reason to be, his skin was crawling, he had a headache, he was exhausted, he was freezing, and –

Wait. Crawling skin.

Oh no they didn't.

Sherlock knows the feeling he's experiencing right now – it's commonly known as "coke bugs". It's a withdrawal symptom.

A withdrawal symptom he hasn't felt for years because he's been clean for a long time. Ever since Mycroft forced him to detox (good, he'd only agreed because Lestrade had told him that, yes, he could help on more cases but only if he became clean), and he'd refused to go to a clinic, so he'd gone cold turkey and it had almost killed him, but he'd been clean in the end.

Even the craving for the drug considerably lessened once Lestrade had proved true to his word and Sherlock could help out the police on a regular basis.

Well, and now and then, before John moved in, when he didn't have cases and the boredom got too much, yes, he had injected a little bit of cocaine, but not too much, and never enough to bring back any withdrawal symptoms.

And ever since he and John became what normal people called "friends" he hasn't touched his secret stash once.

So why is he feeling like he just came down from a massive high?

There's only one explanation: Someone must have kidnapped and drugged him. Maybe before they reached the crime scene.

But this means...

A wave of anxiousness hits him. Where's John? What have they done to John?

And who are "they" exactly?

He shakes his head. The most important question he has to answer right now is: Where is he and how does he come out? Ever since he came back, he's been entirely too sentimental.

Forget about John, at least for the time being. No use crying out for him.

A dark room, he with the knife in his hand, a young man bound to a chair, bleeding, crying, demanding where his girlfriend is. She's safe, but he doesn't need to know that. "That's none of your business right now" Sherlock says, coldly. "Tell me who your boss is..."

No use thinking about that now, either. He shoves the memory back into the room labelled "Being Dead" and looks around the one he currently occupies.

It's dark, it's cold, it's gloomy, ugly, and – abandoned.

Of course. The curtains are barely holding together, there is no furniture, there is mildew on the wall, it smells –

An abandoned building, like the ones his homeless network likes to occupy. The last place for a person without hope to go.

A strange place to keep him, surely, but elegant in its way. Who'd come looking for him in a place like that?

But...

No one's guarding him. Sherlock has developed a sense that tells him when anybody's near him – he had to, after –

A hand clasps over his shoulder. "Hello, there" a voice says in Spanish, "I guess I finally found the lonesome vigilante..."

No. Nonononono. Just no. The presence is more important.

So he stands up – he's been lying on the floor the whole time, how embarrassing – and slowly – his body doesn't seem to want to obey him – walks to the door. He opens it. Looks out.

There's no one there, either. In fact, the whole building seems, as before stated, abandoned.

Good. Or not. Whatever. First, he has to get out of her. He only hopes he's still in London. Then he has to find John.

And probably call Mycroft for help, though he doesn't really like the thought.

So he sneaks out of the room and down the corridor, finds the stairs –

The place must have been a mansion once, it's impressively big. Most likely considered to be haunted, which would explain why no one wants to live here. Come to think of it, it would be a great place to hide someone.

"Trust me, nobody will hear you scream, now tell me who you are and why you're tracking down our associates..."

Sherlock comes to the entrance hall – it has taken forever to reach it, really, he feels so weak, like he hasn't slept or eaten for weeks, and the skin crawling and the headache haven't got much better.

Then he sees a shape moving in the corner of his eye and turns around as quickly as he can. Which isn't that quick, really.

He relaxes when he realizes it's only a dirty mirror.

But then –

Then he sees himself and runs – or does something very similar, he can't really run at the moment – to the wall so he's standing in front of it, and his breath catches in his throat.

Because he's only wearing a torn, dirty, faded T-shirt that might have been blue once upon a time, and an equally bad looking pair of jeans. No wonder he's freezing.

Because he's pale, and thin, even more so than when he returned, and he looks like a corpse, and it seems he hasn't taken a shower or washed his hair in years.

Because there are tiny little marks from needles all over his arms.

Because it doesn't take his powers of deduction to realize –

That the person he's looking at has been a cocaine addict for years.

Author's note: Yes, this idea simply came to me, as they do, and no, I couldn't resist. And because there isn't too much going on at all, with him waking up a cocaine addict and all, I decided to put a case in. And him dealing with the whole tracking-down-Moriarty's-web-while-being-dead-to-the-world thing. Because.

Please review, I'm curious to know what you think.