Torn across the city as the Fire Nation closes in, the team must reunite to save Ba Sing Se — and Zuko must decide where his real loyalties lie.

To uncover a mythic library that could hold the key to defeating the Fire Nation, the team is forced to ally with an old enemy.

At a high-stakes earthbending match, Aang discovers the teacher he's been seeking. Painful memories emerge after Zuko befriends a farming family.

Toph puts Aang's skills to the test. In the streets of Ba Sing Se, Sokka searches for a missing friend, while Katara lives a double life.

Zhao leads the Fire Nation into the North with a bold plan to weaken the Water Tribe. When the battle takes a dark turn, Aang enters a powerful state.

When the group lands in the Spirit World for a rescue mission, they come face to face with dangerous threats, painful memories and a mysterious entity.

In captivity, Aang meets a king with a taste for games. To find their friend, the siblings must navigate a dark tunnel — and put their differences aside.

News of a traitor puts the trio at odds in Omashu, where a mechanist and rebels with a charming leader muddle their plans to protect the Earth Kingdom.

An Airbender comes to grips with his new reality as war erupts. A century later, a pair of Water Tribe siblings make a discovery that changes everything.

As an attack on the Northern Water Tribe looms, Katara challenges a master Waterbender, Sokka meets a princess, and Aang takes Kuruk's words to heart.