Avatar Aang: The Last Airbender

Thirteen years after the end of the Hundred Year War, Avatar Aang and his friends help rebuild the world by establishing Republic City as a home for people of all nations. While restoring a desolate Air Temple, Aang is ambushed by the Denied, a group of non-bending warriors searching for a relic tied to the mysterious Avatar Sonam. Although he repels the attack and saves the temple, he travels to Republic City to warn Katara, his longtime girlfriend and the city's council representative.

Concerned about the future of the Air Nomads as their last surviving airbender, Aang consults Avatar Xian, who reveals that Sonam was a forgotten Avatar whose staff could channel the energy of the Spirit World and grant its wielder immense power. Believing the Denied seek the staff, Aang reunites with his friends—Sokka, now living in the Southern Water Tribe; Toph, who trains earthbenders; and Fire Lord Zuko, ruler of the Fire Nation—and journeys to the staff's last known location atop Mount Baihu.

At the mountain, the group discovers the frozen body of an airbender. After rescuing him, they learn he is Tagah, a former non-bender whom Sonam granted airbending through her staff. Tagah persuades Aang to accompany him to a hidden island in the Endless Ocean, where the staff is said to rest, despite Katara's suspicions. As Aang is taught by Tagah the forgotten airbending techniques, he begins to hope that the Air Nomads can one day be restored. Although Tagah shares this vision, he expresses resentment toward the other bending nations. While sailing through the storm surrounding the island, the group is pursued by the Denied. As Sokka, Katara, Toph, and Zuko fend off the attackers, Aang and Tagah use airbending to clear a path through the storm. Tagah's increasingly ruthless methods deepen Katara's distrust. Katara asks Aang to abandon his pursuit of the staff due to the dangerous mission and her reservations about Tagah, but Aang dismisses her concerns, prioritizing his desire for the staff over the safety of the crew.

On the island, Aang attempts to retrieve the staff by wielding all four elements. Tagah follows but is confronted by Katara. Revealing his true intentions, Tagah attacks and kills the group, including Aang, and steals the staff with the plan to use its power to grant airbending to the Denied and restore what he believes to be Air Nomad supremacy. After Tagah departs, Sonam's spirit appears to Aang and reveals that she hid the staff and imprisoned Tagah after he became consumed by trauma following the slaughter of the Air Nomads during the rise of the Earth Kingdom. Landing in a pool of spirit water, Katara revives herself from Tagah's assault and then revives the others, allowing Aang to open a portal to the Spirit World in pursuit of him.

Finding the Spirit World thrown into imbalance, the group seeks the aid of the spirit Gorillavark, who helps them return to Republic City, now under attack by the newly empowered Denied. While his friends battle the invaders, Aang confronts Tagah and reclaims the staff. Enraged by Tagah's accusations that he failed to protect the Air Nomads, Aang briefly succumbs to a corrupted Avatar State that threatens to consume him. Before delivering a fatal blow, memories of Monk Gyatso restore his resolve, and he instead destroys Sonam's staff. Its destruction strips the Denied of their airbending and causes Tagah to fade away. Before disappearing, Tagah is persuaded by Aang to forgive himself, allowing Aang to forgive himself as well.

In the aftermath, Aang begins building a new Air Temple near Republic City. Speaking with Sonam's spirit, he concludes that the true legacy of the Air Nomads lies not in power but in their values, which can be passed on to future generations. Together, the group welcomes new Air Nomad acolytes and discovers a surviving herd of sky bison, which Aang recognizes as the "original airbenders".