Weeks after the fall of the Earth Kingdom, Aang and his friends must infiltrate the Fire Nation. Katara meets her father for the first time in years. Zuko returns home, but is uneasy with his newfound reputation.
After deciding he's the least valuable member of the team, Sokka seeks an apprenticeship with a sword-master. The rest of the gang tries to adjust to being without him. The imprisoned Iroh may not be as beaten as he seems.
Zuko makes a decision about his future. Aang reunites with many of his old friends in a full-scale invasion of the Fire Nation capitol to coincide with an eclipse which will remove the Fire Nation's powers.
Zuko has joined up with Aang's group and is now ready to teach Aang fire bending. Unfortunately, Zuko has found out that he has lost his ability and must now relearn it. Zuko and Aang travel to find the original source of fire bending so that they both can learn from The Firebending Masters.
Sozin's Comet is only three days away. Zuko tells the others what the Fire Lord plans on the day of the comet and the gang realizes that they must stop him before then. But Aang doubts that he can do what is expected of him.