The plot is close to Kevin Costner's "Dances With Wolves", with a visually stunning sci fi edge. Injured soldier takes on a mission to live among the natives. First native he meets happens to be the daughter of the local native spiritual leader with whom he falls in love.
He soon realizes the true enemy is his own people who threaten the natural web of life. He learns from the locals that the land is not for expanding personal wealth but is the very root of our shared existence.
He warns the natives too late that they will soon be forced out with overwhelming military might. When the invasion begins, he leads the charge against them. The heroic result seals his fate as he "goes native" for good, leaving his old life forever behind.