Audiences who'd rather not scratch their heads are best advised to stay away from this group of films, in which things are never quite what they seem. In the world of the mindbender, characters can exchange identities, chronological order can be reversed or corrupted, and dream sequences can effortlessly drift into reality. The pretzel logic on display in these movies may be hard to decipher, but it's sure to spur on hours of heated discussion once the credits roll.