In the near future, humanity decides to abandon Earth after numerous cataclysmic events. Human society is re-established on a habitable exoplanet known as Nova Prime outside of our Solar System. Meanwhile, the creatures of Earth continue to evolve, apparently without any human interaction.
Set one thousand years after humanity's resettlement, a peacekeeping organization known as the Ranger Corps is trained by a wise - but stern - General named Cypher Raige. Under his command is a young recruit named Kitai, a rebellious teenager with a knack for mischief. Kitai is also Cypher's son, and the father is frustrated at what he sees to be a lack of discipline.
Cypher's wife, Faia, urges him to see Kitai's behaviour as a longing for his father's love and a plea for attention. At her behest, Cypher takes Kitai on a mission to Earth. The ship is damaged in an asteroid field and crash lands on the planet, killing all but Cypher and Kitai, who are seriously injured in the accident. The two must retrieve an emergency beacon by embarking on a perilous journey across uncharted terrain. Dangerous animal species now dominate the planet, as well as an unstoppable alien creature that escaped during the crash, to signal for help.