David Letterman interviewing Anne Hathaway's brother.

Anne Hathaway was on The Tonight Show Late Night with David Letterman last night to promote The Dark Knight Rises, and Letterman told her that he saw the film already and complimented her work as Catwoman. That should have been it. There shouldn’t have been anything else. But there was. There might have been a really terrible, unforgivable spoiler. And it may have been a joke, or it may have been a genuine slip. But damn it, Dave, we don’t joke about spoiling the third and final installment of Christopher Nolan’s magnificent Batman series.

I’ve included the video after the jump, and I believe the spoiler is right around the 9:20 mark, or just don’t watch it if you want to bury your head in the sand. People seem to think the slip-up was genuine. I mean, I love Letterman – he’s one of my favorite comedians of all-time – so I know that he’s one of the greatest when it comes to playing head games about something like this. But I just don’t know.

I won’t tell you the spoiler, but feel free to discuss it in the comments while I try to bleach my brain stem.