Plot: In this fantasy version of the world, everything is divided into four nations, each with their own sub-ethnicities, but still. Among the nations there are those born with the ability to bend, that is learn to control one of the four elements, via telekinesis and martial arts, from which each nation takes its name: water, earth, fire, air. The nations are supposed to coexist in balance just as humanity as a whole is meant to coexist with the spirits of nature and the earth, but it not always so.
The greatest war of conquest ever waged has been raging for over one hundred years between the industrial empire that is the Fire Nation and the rest of the earth. Only the avatar, the continually reincarnated spirit of the earth itself with the ability to bend all four elements and more, could rally the force to stop them, but the last avatar, a Fire Nation warrior died mysteriously before the start of the war, and nation which the avatar was supposed to be born into next, the Air Nomads, was the first attacked and wiped out by the Fire Nation.
One day on the edge of the south pole two siblings discover the reincarnation of the avatar a young twelve year old boy named Aang. Aang is reluctant to take up the mantle of chosen savior, but with the help the ethics he was given as a child and the new people who will become his friends, enemies, and everything in-between he becomes the hero not of the world, but rather the first among many.
Verdict: That long, but needed plot summary is nothing anyone has not heard before, but then this series is not a new idea. This series is literally the hero of a thousand faces put to the small screen. It is the epic fantasy coming of age story. It is Harry Potter, Lord of the Rings, Star Wars, Dragonball, Dragonball Z--actually if Star Wars's writing cross with Dragonball Z's magic is a pretty good analogy for the series a whole. What makes this one so great is just the way it is handled compared to all those others.
No one is overtly evil because good is dumb that's why, not even our final villain , and the cast is far more diverse and well rounded than any other out there telling this story. This is the hero's journey to start kids on bar none due to how it is generally humorous in tone, yet always manages to transition so well into drama (and there is some real drama--see below). It won't say anything new, but it does say something old in way that has been too long and coming. Buy it.
Facts: This series is three seasons of 20 half-hour episodes. There is some unfortunate filler, but not much. This was produced by Nickelodeon. It has a sequel series called Avatar: the Legend of Korra, which I have heard some good things about. That show is 12 half-hour episodes. There are also a set of three sequel graphic novels called Avatar: the Promise, which are worth reading if you liked the series and the world. Do not see the live action films. They are garbage, even if they were not horribly racist, they would still be garbage.
In terms of voice cast this one got some great talent, Jason Isaacs, Mae Whitman, Jessie Flower, Mako, Mark Hamill, Clancy Brown, Dee Bradely Baker and more are in this cast.