Avatar: The Last Airbender Season 3 Episode 1 : The Awakening
Aang awakens to find himself gravely wounded from the battle in Ba Sing Se at the end of Book 2 on board a stolen Fire Nation ship with his friends. He is shocked and dismayed to discover that the world believes him to be dead. Zuko and Azula are welcomed home as heroes, where Firelord Ozai congratulates his son. After a great deal of persuasion, Aang agrees to keep his existence a secret. In the end, he burns his glider in the lava of the volcanic crescent shaped island that he visited in Book 1 when he spoke to Avatar Roku, the Avatar before him.