James Cameron's immersive 2009 epic — the biggest box-office smash of all time — is a model for what 3D can do. It's 2154, and the Earth is dying. To survive we need a mineral called Unobtainium. To get it we travel to the alien moon of Pandora and abuse its natives. They are the blue-skinned, yellow-eyed, 10-foot tall Na'vi, who hug trees but hate on intrusive humans. Jake Sully (Sam Worthington), a crippled ex-marine on the Pandora mission, loses his heart to Neytiri (Zoe Saldana), a Na'vi princess. How does that happen? Dr.Grace Augustine (Sigourney Weaver ) and her scientific team have mixed human and Na'vi DNA to create avatars to infiltrate Pandora. The computerized creation that is Pandora overflows with beauty and terror (those banshees are a wonder). The last third of the movie, a battle between the Na'vi and their human destroyers, is a groundbreaking blend of digital and live-action. It's also 3D heaven.