This episode is part of the Avatar Book Two - Earth
Avatar The Last Airbender Episode Guide ~ via Wiki
After leaving the desert, the group and Suki attempt to lead a couple who are expecting through the dangerous Serpent’s Pass. While Zuko and Iroh are on the ferry to Ba Sing Se, they meet Jet, who is trying to turn his life around. Jet takes an instant liking to Zuko and asks if he wants to join him and his Freedom Fighters.