It looks like The Dark Knight has at least one more surprise up its sleeve. No, it’s not a cameo from Two-Face. It’s Harry Potter.

The IMAX corporation has announced that an extremely short, 15 second trailer for Harry Potter and the Half-Blood Prince will be attached to IMAX versions of The Dark Knight. What good is a 15-second teaser? We have no idea. Usually anything that short is just a logo teaser, but since we’ve all got the logo for Harry Potter in memory by now, that wouldn’t make much sense here. Hopefully it’ll be something more succinctly spectacular.