Avatar is the story of the reluctant hero, Jake Sully, a former Marine paralyzed from the waist down. His twin brother is chosen to participate in a program that genetically links with the Na'vi, an alien species on the planet Pandora, to create a new breed capable of breathing Pandora's atmosphere. This new breed is called an Avatar. After Jake's brother is killed, Jake is chosen to take his place and becomes an Avatar. His mission is to explore and study the planet Pandora. The information he gathers is crucial for the human campaign to colonize this second blue planet.