It's Not You... Wait, It Totally Is

A hilarious practice in Hollywood is to replace a principal actor in the sequel to a very successful movie. Nothing else changes about the franchise: Same cast, same director, same everything... except you. I imagine this must be a semi-devastating phone call to receive from your agent when you're an A-List Hollywood star. "Um, they're making a few changes for the sequel.... Yeah, I know the first one made 600 million dollars... what are the changes? Well, actually, it's just one change."

A few notable incidents of a well-known costar getting abruptly replaced in the sequel:

Terrence Howard (by Don Cheadle) in "Iron Man 2" - I never heard an explanation why Terry was let go. Let's just assume he was a delight to work with.

Bill Murray (by Bernie Mac) in "Charlie's Angels 2" - Maybe they scraped the "ill" and "urray" off the Star Wagons trailer and said "Screw it, call Bernie Mac and Brian McKnight and see who will do it cheaper."

Katie Holmes (by Maggie Gylenhaal) in "The Dark Knight" - You could have replaced Katie Holmes with Anna Nicole Smith's corpse and it would have been a lateral move.