The sound came from downstairs. A muffled voice croaking. John blinked, staring up at the ceiling of the flat's second bedroom. He lay there, waiting. Sherlock did keep rather odd hours, and did rather odd things, but this sounded different. This sounded wrong.

The unsettling noise came again, this time louder, more urgent. John sighed and swung his legs over, sitting up sleepily. "Sherlock?" he said loudly. Maybe it was him. Maybe it wasn't anything to worry about - scratch that. If Sherlock was involved, there was a high probability of it being something to worry about.

John stood up and made his way to the top of the stairs, his bare feet cold against the flooring. He looked downstairs. "Sherlock?" he said again, his voice a bit more irritated now. "Sherlock, I've told you before, I don't want you practicing your escape techniques at night anymore."

The air was still and cool. And silent. Until a third muffled sound broke the silence, and John's patience.

"Alright, coming down now," he mumbled, going down the stairs. "That better not be you, Sherlock."

If only it had been.