In a world shattered by a devastating cataclysm, a young Earthbender discovers she's the new Avatar after Korra — but, in this dangerous era, that title marks her as humanity's destroyer, not its savior. Hunted by both human and spirit enemies, she and her long-lost twin must uncover their mysterious origins and save the Seven Havens before civilization's last strongholds collapse.

Avatar Aang, the world's last Airbender, learns of an ancient power that could save his culture from extinction. With the help of his friends, he embarks on a global quest to find it before it falls into the wrong hands and threatens to upend the peace they sacrificed everything to achieve.

A century has passed since the Fire Nation declared war on the other three nations of air, water, and earth in its attempt for global domination. Aang, the long-lost Avatar, is found by Water Tribe siblings Katara and Sokka and must learn to master water, earth, and fire bending to defeat the Fire Nation and restore balance to the world.