Avatar The Last Airbender The Promise Part 1

Following Fire Lord Ozai's defeat and the conclusion of the Hundred Year War, the Harmony Restoration Movement is established to remove the Fire Nation Colonies in the Earth Kingdom and relocate the colonists to the Fire Nation. Having become the new Fire Lord, Zuko makes Aang promise to kill him, should he turn out like his father.

One year later, Zuko survives an attempt on his life made by Kori Morishita, in protest against the Harmony Restoration Movement. Learning that Kori is the daughter of the Mayor of Yu Dao, the first colony created by the Fire Nation, Zuko travels to the city to confront the Morishita family. He learns that over the last century, the Fire Nation colonists have become deeply integrated with the original Earth Kingdom citizens, to the point that there are now mixed-race families, industries that use expertise from both cultures, and Earthbenders who consider themselves Fire Nation citizens, including Kori. Realizing that the Harmony Restoration Movement would bring an end to this, Zuko withdraws his support for it.

Zuko's decision causes protests from Earth Kingdom citizens, including the Freedom Fighters, who believe that Zuko is refusing to give up the colonies, and prompts Aang, Katara and Sokka to travel to Yu Dao to confront him. Aang's predecessor Avatar Roku urges Aang to fulfill his promise to Zuko, reminding him that his own failure to kill Fire Lord Sozin led to the Hundred Year War happening in the first place. Arriving in Yu Dao, Aang and Katara get into a fight with Zuko and his troops, and Aang nearly goes into the Avatar State, but he is talked out of it by Katara.

Despite seeing the prosperity of Yu Dao for himself, Aang insists that the Fire Nation cannot keep occupying part of the Earth Kingdom if the world is to live in harmony. Katara suggests that Yu Dao be the exception to this rule, but Zuko states that the same should be done for the remaining colonies. Although doubtful, Aang agrees to try to get Earth King Kuei to talk with Zuko on what to do. The Earth Kingdom protestors are unhappy with Aang's decision, having suffered the presence of the colonies for over a century, and give him three days before they attempt to retake the city for themselves. Returning to the Fire Nation, Zuko visits his father for advice.