The 3D extravaganza starring Sam Worthington, Sigourney Weaver and Zoe Saldana is set on Pandora, a distant planet inhabited by the Na'vi a race of aliens with blue skin.
For the past few years the four planned follow-ups have simply been referred to as Avatar 2, Avatar 3, Avatar 4 and Avatar 5.
And details about the four sequels have been more elusive than the element Unobtanium!
