While journeying to the North Pole, Aang, Sokka and Katara explore Aang's former home, the Southern Air Temple. After one hundred years, Aangs returns home to the abandoned Airbender Temple where he faces his past and his future as the Avatar. Aang believes that there is no chance that the fire nations could attack the temple due to its height. In one of the temple room they found statues of avatar in circle formation - The Avatar Circle. Each time avatar reincarnated, it will be in the cyclic element turn of Water - Earth - Fire - Air (just like the episode/book formation).
Meanwhile, Zuko and his uncle, Iroh, have their ship repaired at a Fire Nation port commanded by a rival, Commander Zhao. He told his uncle not to mention anything about the Avatar.
But later, Commander Zhao find out what just happened to Zuko ship from his soldier. The enmity between Commander Zhao and Prince Zuko become clear and leading to Agni Kai (Fire Fighting - Firebender Duel). After a tiring fight, it's end up with Zuko as the winner. Commander Zhao try to attack Zuko from behind after the Agni Kai, but it's blocked by General Iroh. "Even in exile my nephew is more honorable than you" said General Iroh
Back at the temple, desperate for hunger, a winged lemur flew in to the temple. Sokka and Aang chased down the winged lemur. Aang suprised he found that Firebenders was ever been there.
A startling discovery forces Aang to come to terms with what really happened to the airbenders after he found Monk Gyatso dead body. Aang learns of his people's genocide at the hands of the Fire Nation; his anger triggers his Avatar State, which in turn alerts the world that the Avatar has returned, including the avatar temple in the Fire Nation. Soon the Firelord - Lord Ozai would notice that the Avatar has returns.
Meanwhile, Katara try to calm Aang, considering about what has just revealed in front of them. There is no turn back, and it wasn't Aang fault. Katara told him that, he still have family, Katara and Sokka. But when a winged lemur, Momo, joins the group, he offers Aang a new sense of hope. Meanwhile Prince Zuko realizes he has competition when the ambitious Commander Zhao vows to capture the Avatar before him.
