Now that football fans have discovered James Cameron's Avatar first-hand, a new featurette explains the movie's storyline. It also reveals new clips, previously undiscovered creatures... and Sigourney Weaver occupying her alien "Avatar" body. Gallery of gorgeous new creatures below.

First up, I'm glad they cleared up the nagging question of why Jake Sully is being used in this huge military operation anyway, since he's not super trustworthy and defects rather quickly to the alien side. His twin brother is 6 feet under, and they have the same DNA. So sure I guess that works. But what's really interesting are all the new creatures uncovered in this featurette, and we pulled pictures of a few for your enjoyment. To be honest, we like these guys more than anything we've seen before especially that monkey fella.

Avatar will be in theaters December 18th.

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