Sokka accepts a job for a fisherman who is looking for someone to help him out with his fishing. After the fisherman finds out Aang is the Avatar, Aang runs away in response to the fisherman's hostile reaction. When Katara finds Aang, he begins to reveal his life before he was frozen in the iceberg. Meanwhile, after Zuko gets into a fight with his crew, Iroh tells them about Zuko's complicated past, attempting to make both sides understand each other.

Zuko travels by himself to an Earth Kingdom town where he meets a local boy. The two almost become friends, while Zuko suffers from flashbacks of his past.

Aang awakens to find himself aboard a captured Fire Nation ship with a full head of hair and sustaining serious injuries from the previous battle for Ba Sing Se. At his side are Katara, Sokka, and their father Hakoda who recount the events that led the four to the ship and contemplate their next move. Aang struggles to fight his own desire to face the Fire Lord before he is ready. Meanwhile, Zuko deals with his own issues as he makes his long-awaited journey home, with the fear of his father's rejection hanging over his head.

Four days prior the invasion, Aang becomes nervous over his soon-to-come confrontation with the Fire Lord. His anxiety gets the better of him as he begins to suffer from outrageous nightmares and hallucinations. Meanwhile, Zuko becomes upset to learn that he was not informed about a war meeting.

As the invasion force fights their way to the Fire Nation capital, the kids help Aang find the Fire Lord in time for the eclipse. Zuko confronts his father with shocking news.

Aang struggles to decide whether or not he has to kill the Fire Lord and, during the night, is drawn toward an island which disappears before morning. Zuko leads the rest of the group to the Earth Kingdom to meet a tracker whom they hope can find Aang. The Fire Lord crowns himself Phoenix King and Aang awakens on the island not knowing where he is.

While on the island, Aang seeks guidance from his past lives, but is not pleased with what he is told. The island, in fact, turns out to be a lion turtle from which Aang is given the guidance he had been seeking. Meanwhile, after the tracker is unable to track Aang, the rest of the group decide they must find Iroh. While tracking him down, the group meets up with The Order of the White Lotus, a group that transcends the division of the four nations.

Sokka, Suki, and Toph try to stop the Fire Nation's air fleet. Meanwhile, Zuko and Azula duel in an Agni Kai and Aang confronts the Fire Lord.

Aang is on the offensive after getting hit in the back of his scar and triggering the Avatar State. Meanwhile, after Zuko seems to have the upper hand against Azula, Katara is forced to join the fight when Azula resorts to desperate measures.