The year is 2012 and in the busy city of Chicago, Illinois, 18 year old Rinry Hong is given a mysterious letter from her "late" foster father telling her that she is in danger. He claims that the world was suffering from a terrible imbalance that has cursed it throughout many years of chaos brought on by mankind. Only she can save the planet from itself and bring a new balance to the world. According to the letter, the only thing Rin can do is travel hundreds of miles to Tibet in order to meet with some person named Anil, (Mr. Hong's nephew) and he is the only one who can help Rinry figure things out because, according to her foster father's dying letter, Rinry was someone of grave importance to the world. She was something he called "The Avatar".
Little does Rinry know that there has not been an Avatar or benders in the new world for hundreds of years! That sole fact is all thanks to the anti-bender elite, a secret organization known as "The Hunters" who hope to stop Rinry and plunge the world into a sense of normality.