In the year 2154, humans agressively pursue the mining of a planet. A marine is dispatched in avatar form to gather information from its inhabitants, and he begins to question his loyalties.
Writer-director James Cameron creates a richly imagined world filled with wondrous creatures and landscapes. It would have been nice if the characters he created had followed suit and exhibited at least a bit of nuance. As it stands, the story is basically a science fiction version of Dances With Wolves. Avatar falls into some of the same traps, such as having a white hero who ends up leading the natives in battle. The story also hits some very predictable action movie beats.
All that being said, Cameron truly makes you feel the tragedy of the destruction of nature, even though he conveys his themes with the subtlety of a jackhammer. And the movie isn't boring for a second.
The 3-D effects are cool, but they often go hazy if you don't look at them exactly right. I would actually have enjoyed the movie more in two dimensions.