Avatar Roku, an Avatar incarnation, died in a volcano incident and soon after the Fire Nation invaded the world. The Fire Lord at that time, Sozin, wiped out all of the Air Temples knowing that the next Avatar would be an airbender. 100 years had past, and the Fire Nation was winning the war. The new Avatar, Aang, was discovered in suspended animation in an iceberg by two Water Tribe siblings, Katara and Sokka. It was Aang's destiny to stop Firelord Ozai, a decedent of Sozin, from using a comet's power to end the war once and for all. To halt the advances between the Fire Nation versus the rest of the remaining nations, Aang had some help from friends in his quest to master the elements that were left: water, earth, and fire. One was Katara, a waterbender from the Southern Water Tribe was his waterbending teacher, while Sokka was her older brother. Toph was a blind earthbender who taught Aang her martial art, and Zuko, Firelord Ozai's son, originally hunted down Aang to restore his lost honor with his father, but later helped Aang bend fire.
70 years have past, and Aang, the previous Avatar incarnation who was the last airbender has passed on. A waterbender from the Southern Water Tribe is the now the new Avatar. Her name is Korra, a girl who is rebellious, alone, and ready to take on whatever issues or battles she must face. It is Korra's destiny to protect the world as it was for her predecessors. She has three elements mastered: water, earth, and fire. The trouble is, she needs to master air while there are very few airbenders left. Tenzin, Aang and Katara's son, is the only person who can teach Korra how to airbend and it is her mission to find him or risk losing the new world's industrial melting pot, Republic City, to crime and anti-bender revolts.
Can Korra live up to her past life and keep the world in balance?