The security room was… dank. Dreary. Dreadful.

Dark.

Four cabinets guarded two green computer chairs, worn well past threadbare with use with yellow spongy foam sticking up out of the holes, which sat in front of two plastic desks, which sat in front of a row of dead screens.

Sherlock attempted to switch one of the fluorescent lights on, and it began sparking violently. It seemed that it too had fallen victim to whatever power supply cock-up was plaguing the security cameras and most of the cooking appliances since the incident. He thought nothing of it more than mild annoyance. How did electricity work anyway? He'd ask John, but after the solar system incident he thought better of it. He opted to turn a screen on instead, the static illuminated the room sufficiently.

"Why did you call me Steve?" he asked, curiously, "I told you I was Mark."

"You're neither. I prefer Steve."

"You're right. Most people call me Doctor."

"I prefer Steve."

'Steve' sat compliantly in one of the computer chairs, content with spinning around and grinning at Sherlock madly. He had taken, once more, the precaution of handcuffing the far-too-enthusiastic-about-being-questioned man but noted that this still did not make him feel entirely safe.

Thankfully, he had an advantage. But there was no need to give that away yet.

"You were wrong about some things, you know." 'Steve' smiled, shaking his head in an oddly affectionate manner.

"Oh?"

He's beyond stupid if he thinks Sherlock will rise to that.

"River, she's actually their daughter."

Sherlock raised an eyebrow in disbelief. What on earth was he trying to do? An obviously intelligent man, we he trying to purposely irritate him? Or was he genuinely mad?

Very serious tone, no indication of lying. Maybe trying to tell him something. Marriage falling apart, his or theirs, going into the child's death….

All irrelevant, but perhaps he'd be more likely to explain what was in that Police Box…

"The forty year old is the daughter of people who haven't passed thirty?"

'Steve' winced, as if the thought for some reason brought him pain. Genuine pain, no acting. Getting somewhere, somewhere metaphorical possible.

"There was a bit of a mix up. I was," another wince, "Very stupid. Painfully stupid, in fact."

"Oh so you were there now, were you?" Sherlock snapped, annoyed at the nonsense the man was spouting. Gave no outward indication of drug use…

This was ridiculous. Shouldn't humour him, just get to the box. His 'TARDIS'.

"Well yes, just after. I so very nearly got her back…" he looked off into the distance, contemplative. Also genuine.

"And," don't rise to it, play along, keep tone light, we're getting to some sort of cryptic point, "The neglect from her parents then? Those two aren't capable of neglect, they worry too much."

Steve's attitude changed abruptly to defensive, and he stared at Sherlock intensely. He was furious, Sherlock realised. Genuinely furious. No acting. Unless he was very, very wrong which he very, very doubted.

"Well it's a bit difficult when you're nine!" he barked.

Sherlock wanted to scream. Incoherent babbling of a mad man. The worst of all the babbling.

Her grabbed his shoulder and shook him violently, looking him dead in the eyes. The door was to their left, the desks to their right. The room was eight foot by six foot. But still, Sherlock didn't like the idea of him wandering around too freely.

"Enough, the box now. Explain.

'Steve' was smiling again.

"I expect you to doubt, Sherlock, what you saw. But you know what you saw. 'It's bigger on the inside'"

His eyes gleamed, as if he had uttered those words thousands of times before. And it was true, that's what Sherlock had seen. Except, it could not possibly be true.

"A trick!" Sherlock spat, "And if I can get into it I can prove it."

"You need a set of keys for that."

"Like this set of keys?"

Time to unveil the advantage. The cylindrical, heavy device which until recently had resided in the inner pocket of Steve's jacket.

As he predicted, 'Steve's' eyes widened.

"Oh no, no, no, non, nein, no!" 'Steve' shook his head, "Sherlock put that down. No, don't! Give it here! How did you-"

"Easily, "Sherlock sighed, examining the device in as much detail as he could under the light of the static, "What does it do, exactly?"

This was said more to himself than to 'Steve'.

"I saw you, very quickly, flash this and shut the door of that 'TARDIS'. I also saw you use it to undo your handcuffs… But how does it work?"

"Well basically…"

"I'm not talking to you! Shut up!"

The radio at Sherlock's belt, there by John's insistence, crackled into life.

"Holmes? Holmes?" a pause, "Sherlock, pick up the fucking radio now!"

"Yes, John?" he answered distractedly, still focussing on the device.

No response.

"John?"

"I… I don't know. Sherlock I've forgo-"

Sherlock turned it off and threw it over his shoulder, where it crashed into a file cabinet.

"He forgot!" Sherlock harrumphed, scrambling around the desk, moving papers and mugs every which way.

"What was that about?" 'Steve' asked, massaging his wrists.

"If only I… How did you get out of handcuffs?"

'Steve' froze, stuck a hand into his left coat pocket and produced the device/'screwdriver'.

"You… You gave me back my screwdriver. Why did you do that?"

"I most certainly did not!" Sherlock yelled, suddenly doubtful. He noticed he was holding a pen now.

"Screwdriver?" he added incredulously with an exasperated expression, and began rummaging around the desk again.

"A sonic screwdriver, it works in many ways. Not on wood though, it doesn't do wood. Well, actually that's a funny story-"

"Shut up! I'm interrogating you! Now, why have you got a tally on your arm?"

That cut the 'Doctor off any giddy rambles. Very abruptly. Curiously abruptly.

But Sherlock suddenly noticed the knife in his own hands. The hard plastic food-court disposable knife he had been trying to find. Why had he been trying to find…

The Doctor gulped, cutting off his thoughts. A thin film of sweat coated his forehead.

"Sherlock, we need to turn around."

"We need to turn around?"

"To the left Sherlock, to the left."

"Oh would you shut up!" Sherlock barked. He was shaking, the after effects of fear caused by adrenaline. Nothing made sense, and this worried him. It worried him beyond belief. Fear coiled like a worm in his gut and worked its way to his throat. But he would not move. No, not before getting answers.

No matter how many objects he picked up for no reason, he was getting answers.

"The box screwdriver, now." He swallowed, shaking his head violently, outstretching his free hand/

"Sherlock!" Steve bellowed his name so loudly it left tinnitus, "Listen, stop it and listen."

For once in his life, Sherlock stopped it and Sherlock listened.

"You saw an impossible room. I am an impossible man. River is their daughter. They had her four years ago, raised her as children fifteen years ago and met her three years ago. I am over a thousand years old, I travel space and time in that impossible room, I am alien, I am a Timelord. I've been to the end of the universe and I've restarted it. They are my friends, she is my wife. Amy remembers extraordinary things. Rory was a Roman soldier. River was made within the time vortex, she is part Timelord, she is very good with a good with a gun. And I know you do not believe this and that you will never want to accept this and that you think I'm mad, that you think this is a fairy-tale, a series of ramblings, a collection of nonsense and I. DON'T. CARE. The only thing that matters is that you are going to turn left this instant and be bloody happy you did so!"

And Sherlock turned left.

And Sherlock gulped at what he saw, and began to tremor. His pupils dilated, his breath became laboured and his wits failed him. He had never felt fear like this before in his life.

And in this he could only manage three stumbled and difficult words.

"Alien, you say?"