Set more than a decade after the events of the first film, the story resumes on the lush moon Pandora. Former human-turned-Na'vi, Jake Sully, now lives a settled life with his partner Neytiri and their children. As the family grows, they find peace among the forest-dwelling tribes, learning to coexist with the myriad creatures and complex ecosystems. However, the return of humans to Pandora brings with it the inevitable clash of civilizations and ideologies. Despite their efforts to maintain harmony, Jake and Neytiri's family is threatened by the resurgent human forces bent on exploiting Pandora's resources.

In response to the escalating conflict, the Sully family is forced to leave their home and seek refuge with the Metkayina clan, Na'vi who live in harmony with Pandora's oceans. Here, the family must adapt to a new way of life and the cultural differences of their aquatic kin. The oceans of Pandora hold many secrets and untold riches, further enticing human exploitation. As tensions rise, Jake finds himself at the forefront of a fight for survival, as he attempts to unite the Na'vi clans against the technological might of the human invaders, all while grappling with the challenge of protecting his family and respecting the sacred balance of Pandora's diverse ecosystems.