Prince Zuko attacks the Southern Water Tribe seeking to capture the Avatar, Aang. Katara and Sokka fly in on Appa to save Aang from the Fire Nation.

Sokka and Katara, two teenage siblings living in the South Pole, discover Aang and his pet flying bison, Appa, trapped in an iceberg. After Katara accidentally frees him, Aang learns that he is the last surviving Airbender...