Sherlock slid down the wall with a groan, still coughing, and Sally forced herself over to him, even though all she wanted to do was curl up and cry the tears out of her eyes. She was used to things being blurry when she didn't have her lenses, but this was beyond stupid; it was like the whole world was made of ripples of dim colour.

"You alright?" she said, dropping down beside him. He tried to nod, but the coughing went on and on, until he was bright red. His face, like hers, was covered in tears.

"Are you sure?"

The coughing faded slightly and he nodded again. She brought up a hand to rub her throat absentmindedly, and then scrubbed at her eyes with the heels of her hands. The world came a little more into focus. They were in yet another room, dimly lit so that she couldn't make out much except for Sherlock, and that was because she knew he was there. She sniffed, but her nose refused to stop running. Sherlock swallowed.

"Well done."

She acknowledged the praise with a nod. "You did well too."

He shook his head. "Should have been faster…couldn't." He was cut off with another cough. "Couldn't get through the plastic with my teeth…"

"You sure you're alright?" She felt stupid, repeating herself, but the thought of what John would do to her intestines if something happened to Sherlock was slightly chilling.

He nodded. "Do stop being tedious. I simply inhaled more of the gas when I had to take a deep breath after holding it for so long with the ball in my mouth."

"Well you look like a sickly beetroot, so I thought I'd better check."

Through the tears she was fairly sure he was glaring at her. "I bear no resemblance to a root vegetable, ailing or otherwise."

She snorted. "Whatever. What can you see in here?"

He rubbed at his eyes, sniffed and looked around. "Nothing…"

She tapped the floor and realised it was metal, chilling her hands; already she felt cooler, her body temperature dropping. The sensation was rather pleasant after the heat of the second test.

"Is he going to say anything?" she said, looking at the ceiling. "Or is this one of those ones where we have to work out where the door is?"

Sherlock frowned. "I don't know – there's nothing in this room to deduce." He squinted, blinked a couple more times, and then went into the corner and came back with a small bottle of water. "It might be another chance for us to sleep."

She sipped from the bottle and passed it back to him. She knew she was still dehydrated slightly, but now the test was over the need to pee was intensifying. Still, she drank, because she didn't know when she'd get another opportunity.

Soon the bottle was empty. Sherlock set it back down and leaned back against the wall with his eyes closed, although he wasn't sleeping – the way the tips of his fingers pressed together told her he was thinking. She crossed her legs, uncrossed them and drew them into her chest.

The worst thing about needing to pee was it became the only thing on her mind. Whenever she moved it was uncomfortable, until eventually she couldn't take it any more. She made her way to the empty bottle and quietly unscrewed the cap, but the noise alerted Sherlock; he opened his eyes and looked at her curiously.

Embarrassed, she resorted to nastiness to cover for the blush spreading along her cheeks. "Are you just going to stare at me, pervert?"

He stiffened, sitting up straighter, but turned away. She got the feeling he hadn't known what she'd been doing before, and felt guilt mix with her embarrassment and anger. This was degrading – it was humiliating. Moriarty could be staring at her right now and she wouldn't know it. Also, she wasn't well-equipped for this kind of task – peeing in anything smaller than a bowl was insufferably difficult.

She finished quickly and with a minimum of mess, and then screwed the bottle top on. Her cheeks were burning as much as her eyes now, so she rolled the bottle away; out of sight out of mind.

Sherlock was still facing stubbornly away from her. "You don't need to go, do you?" she said hesitantly.

"Already went," he said stiffly. "In the room before the balls, while you were asleep. Now don't bother me, I'm thinking."

It was an hour later Sherlock suddenly gave a start and turned to face her. In that time Sally had dozed a little and decided she was hungry again, and, when her eyesight had cleared of tears, had gone round the room four times. It was like her life was so bizarre it had to be a dream, but she couldn't get to sleep for long enough to escape it.

She didn't bother asking him what it was – she knew he was going to tell her anyway.

"The temperature!" he said. "The temperature in this room is slowly dropping, I'm sure of it." He put a hand to her forehead and nodded. "You've got colder, much colder. The air too – soon our breath will start condensing."

She felt a sharp stab of fear. "Is he going to freeze us to death? Is it a test?"

Sherlock shook his head. "If it was a test he would have explained the rules. I can't understand why then he'd leave us…maybe if…"

He did that thing where he trailed off again, lost in himself. "Maybe it's like preparation for the next one," she suggested without much hope. "You know, soften us up for the next round."

To her surprise he seemed to agree with her, nodding to himself. The corner of his mouth twitched up slightly. "Clever of him. Very clever."

"So, what do we do?" she said. "How far do you think it's going to drop? I wouldn't put it past that man to lose us a few fingers or toes."

"We conserve body heat," he said stiffly, pulling at his coat. She felt her heart drop a couple of centimetres.

"Please not like in the cheesy novels…"

He stared at her. "I'm afraid I'm unaware of whatever literature you're referring to."

"You're not going to make us strip and shove our hands into each other's armpits or something?" He looked positively horrified; so much so she wished she hadn't said anything.

"I doubt it'll come to that," he said eventually. "Besides, stripping would be counterproductive in this case – Moriarty doesn't want to kill us yet, we're better keeping our clothes on."

"Well. Good." There were a couple of awkward seconds. Now she knew it was happening the air did suddenly seem very cold – she was only wearing a pair of trousers and a jumper, casual clothes designed to stand the outside air, but not really made for really cold conditions. Sherlock had his coat, but underneath that there could only be a shirt, and his trousers were probably no better than hers.

"The important thing is to keep our hands warm," he said, still looking at her like she'd sprouted fangs and extra eyes. "We'll need them for the next task, most likely; when they start stinging or feeling stiff yes, put them under your arms, your own arms."

She did so, then pulled her knees up to her chest and curled up small – she remembered from science lessons she had to minimise her surface area. Sherlock moved slightly closer to her, and she felt his presence warm the air slightly on her left side.

She didn't speak, and he didn't speak. They just sat, just existed, and she felt herself growing more and more lost in her thoughts, which were all she had for real company here. What if it got even worse than this? Was her breath misting in front of her, or was it just the bad light and her imagination tricking her? What if she never got out? Would anyone miss her? How long did they have to stay in this place?

Her nose grew cold and heavy, so she leaned forwards and tried to tuck it between her knees. She was shivering now, only slightly, but enough for her to feel uncomfortable and tired. She moved closer to Sherlock until their legs almost pressed together, and saw him flinch away slightly from the contact. It made her slightly annoyed, but Sherlock never really wanted to touch anyone, so it probably wasn't just her.

Her toes began to tingle, and she wriggled them in her shoes, desperately trying to get feeling back into them. Her breath was definitely misting now, forming small puffs every time she exhaled; she watched the patterns dance and remembered the times she'd pretend she was smoking as she walked along, when she was eleven years old and no doubt looked ridiculous.

Finally though she turned to Sherlock, to suggest they try running around or something to generate more heat, although it was probably already too late. Her heart gave a little stutter of panic when she saw him – his eyes were closed and his head had fallen sideways onto his shoulder, his hands dropped down to his side. He was clearly asleep, and she knew sleep was bad in this situation, anyone knew that…

She elbowed him sharply in the side, and he gave a jerk and sat up, scrambling back into the curled up position they'd both adopted.

"When was the last time you slept for more than ten minutes?" she said accusingly, seeing how his lips were tinged slightly blue – why did he have to be so bloody skinny?

He muttered something and yawned. "About four days. Had a case and didn't have time to sleep properly before all this happened…"

He trailed off again, and she kicked him to keep him focused, perhaps a little harder than was necessary, because sometimes Sherlock Holmes really was an idiot. "Why didn't you sleep in the other room? You know, where it was warm?"

Sherlock muttered something that sounded like 'didn't need to' or 'didn't want to' and she was forced to realise he was crashing bloody fast, and she needed to do something. Her eye fell on his coat, and the ridiculous statement she'd come out with before popped into her head. Surely…yes…

She pulled the coat off him – he looked like he barely noticed – and quickly threw it over both of their heads so it was like a tent, supported by two human poles. It was long enough to cover down to her shins if she curled up small, and immediately they were enclosed in a bubble of air that became muggy and stuffy, but wonderfully warm. She was rather proud of her idea, so much so that when Sherlock's head fell onto her shoulder she didn't shove it away, only wished that John Watson would come and find his boyfriend quickly and take him home, because the man was completely hopeless.

AN: I'm thinking of changing the title of this to 'Fun House', should I?

Thanks for reading! Reviews, suggestions and constructive criticism very welcome.

To be continued.