The storys protagonist, Jake Sully (Sam Worthington), is a former Marine who was wounded and paralyzed from the waist down in combat on Earth. Jake is selected to participate in the Avatar program, which will enable him to walk. Jake travels to Pandora, a lush jungle-covered extraterrestrial moon filled with incredible life forms, some beautiful, many terrifying. Pandora is also home to the Navi, a sentient humanoid race that are more physically capable than humans, although considered primitive.