In a traditional oriental world of great nations and elemental magic, there exist four main nations, each taking their culture from the four dominant elements of the land: air, earth, water, and fire. Each nation draws much of their background and culture from their respective element. The groups are the Air Nomads, the Water Tribe, the Earth Kingdom, and the Fire Nation.
In addition, some members of the elemental nations have the gift of “bending” their tribe’s element, or manipulating it to assist the bender. There are four types of benders- Airbenders, Earthbenders, Waterbenders, and Firebenders.
The four cultures were able to live in peace and harmony for many years. This peace was shattered when the Fire Nation declared war on all the other nations, and embarked on a rampage, conquering the other nations. The other nations fought back, but the Fire Nation had become by far the most powerful of the four, and one by one cities began to fall. As the nations were pushed back, they began to call for their last hope- the Avatar.
The Avatar is the one human with the ability to master not one, but all four of the elements. Only one Avatar lives at a time, and this bender is charged with helping to maintain world peace. When one Avatar dies, he or she is reincarnated into the next cycle. The three collapsing nations were expecting the Avatar to step in and save them. However, the Avatar vanished, and never reappeared in a new body.
100 years later the long war is coming to an end, with the Fire Nation closing in on the last of the nations. The Air Nomads have been completely wiped out, their temples unvisited for a century. The Water Tribe, already split into northern and southern, has retreated to the furthest edges of the globes, the North and South Poles. Only the staunch Earth Kingdom remains, although they are fighting a losing battle, with most of their cities captured. The Avatar has not been sighted in over 100 years, and many people believe that the cycle was broken somehow. The future looks bleak for everyone except the conquering Fire Nation.
Then one day, two young members of the Southern Water Tribe named Katara and Sokka discover a young 12-year old Airbender named Aang, along with his giant flying bison, Appa, who have been frozen in stasis within an iceberg for 100 years. It’s surprising enough that Aang is a member of the Air Nomads, a supposedly extinct people, but after some poking they discover he is also the missing Avatar!
Now that he has returned, Aang must evade capture and master all four elements. Then, it will be possible for the Avatar to confront Fire Lord Ozai, defeat the Fire Nation, bring peace, and finally end the long 100-year war.