I thought I knew. I'm sorry. It's as much of a mystery to me as it is to any of you, now.

[ The feverish delirium has Castiel leading John in slow, wobbling circles. He should get to shelter, return to the bunker, try to put something between himself and this not-quite anomaly, but the thought just doesn't occur to him. ]

Mary? [ Right, his wife, who died and stayed dead some time ago. ] I can't make that call, John. It's not my place.