DATV froze during dialog

Near the end of Act 2 of DATV, and - until now - I have not had any technical issues. That's the good news. And thanks for that! Until now, the game's been running great.

And now here is the bad news. I'm at a cutscene where Rook is talking to someone, and the screen froze. Rook is just standing there. I am playing on Xbox. Hitting B brings up the "skip" option, but hitting that does nothing. None of the other buttons or triggers do anything. I tried removing and reinserting the disc. Did not help. I removed the disc, shut down the Xbox, restarted the Xbox, reinserted the disc - and still nothing. Rook is still frozen. 

I can't do anything. Can't reload an earlier save. Can't restart the game (which would be heartbreaking, because I'm so far along). The screen froze, and has stayed frozen.