"There was what?" he demands. He may not have seemed angry before, but it looks like that's changing.

It's misleading, though. He's not actually angry, per se. He's frustrated because he doesn't know what to do, and the kid seems just as lost, which means he's the one who has to take charge because he's the adult here, but he'll just fuck it up because that's all he's good at, and those feelings are being projected outward as anger because anger is simple.