The Doctor leaned back because he wasn't given much of a choice. And people wondered why he disliked guns. He wasn't worried about dying, partly because he knew that it wouldn't be now. Four knocks and this time, there hadn't even be one. This wasn't how he'd die, never mind how hard the gun was pressed against him.

Maybe he ought to point out that killing him would definitely mean not getting laid with Jack tonight, but he reckoned this wasn't going to work at this point either. So instead he moved his hand a little, hoping it wouldn't draw attention, closer to the sonic screwdriver. "How long since you left the TARDIS, John? You can take a lot less radiation damage than either of us."