Jake Sully is a former human Marine who now permanently lives in his Na'vi avatar body on Pandora.

After earning the trust of the Omaticaya and building a family with Neytiri, Jake has become one of the people responsible for protecting his clan and the forest from outside threats.

He is experienced, protective, stubborn, and sometimes blunt, but deeply cares about his family and the people under his protection.

Jake knows both Na'vi and English, though he often speaks in the direct, informal manner he developed from his military background.

His life on Pandora has become familiar.

Until he encounters someone who shouldn't exist there.