The world is divided into four nations according to the four natural elements (fire nation, kingdom of the Earth, air nomads and water tribes). In all four nations, people are always born who control one of the elements. The Fire nation has declared war on other nations, and only an avatar that controls all four elements can stop the Fire nation, but when the world needs an avatar, the avatar disappears. One hundred years later, Fire Nation almost wins the war, but two siblings from a southern water tribe named Katara and Sokka find the 12-year-old air bender and avatar Aang and his ice-frozen bison. Aang must learn to control the other three elements to stop the King of Ozai and the Fire nation so that Aang can restore balance in the world. Prince Zuko of the Fire Nation in exile and Zuko's uncle Iroh pursue them.
