In another age, power is balanced among four great nations: Water, Earth, Fire, Air. Leaders of each nation are able to manipulate - bend - their native element. Only one, the Avatar, whose spirit is reincarnated through the years, can master all four elements - and is the only one who can maintain the world order. When the Avatar disappeared a hundred years ago, the Fire Nation attacked. All hope was lost. . . until the arrival of Aang, a twelve-year-old Airbender, who reveals himself as the new Avatar. The fate of the world now lies in his hands.