We’ve got it on good authority that the main cast of The Hangover will reunite in the sequel…all except for one.

Don’t worry - Zach Galifianakis and Bradley Cooper are definitely returning. Justin Bartha, the film’s hapless groom, and Ed Helms (the dentist) are also coming back. Even Ken Jeong (whose scene-stealing moment lives in movie infamy) and the film's bride, Sasha Barrese, will reprise their roles. So, who are we missing?

Heather Graham won’t be back in the sequel. Warner Bros. says the script “doesn’t allow any room for her character to show up.” Bummer.

However, we did get one juicy tidbit from Barresse. She says moviegoers can expect “the best cameo you’ve ever seen in your entire life.” Better than Mike Tyson? Doubtful.