[Crane, frankly, wouldn't have been able to do anything to prevent it happening even if he'd realised fast enough what was going on. One moment, he was upright and somewhat irritated and apprehensive. The next, he was slamming against the bottom of the stairwell, having thumped quite painfully against a couple of stairs on the way down. He could taste blood in his mouth, and his right arm was bent in a way that was not all that natural.]