The Empire Strikes Back - Darth Vader is Luke's dad!

 The Sixth Sense - He's really dead!

 Citizen Kane - It's a sled!

 Psycho - Mother Bates is dead - and he's the killer!

 Planet of the Apes - They did it! They blew it up! Damn them all to hell!

 The Crying Game - She's a he!

 The Usual Suspects - Verbal Kint is Keyser Soze!

 Fight Club - They're both the same guy!

 Seven - It's her head in the box!

 What Lies Beneath - Her husband's the bad guy!

 Basic Instinct - She is the killer!

 The Others - They're all dead!

 Jagged Edge - He is the killer!