The film is set in a near-future world where society has fractured into two distinct classes: the highly mechanized, technology-dependent metropolises, and the harsh, dangerous wilderness zones known as The Gorge, remnants of ancient disaster sites where advanced tech fails.

The story introduces Jax (Miles Teller), a former elite military operative who now works as a "Cleaner" a high-risk job involving retrieving valuable, proprietary technology left behind in The Gorge. Jax is cynical and emotionally detached, having lost his family due to the societal collapse caused by the technology he now retrieves.

Jax is hired by a powerful, secretive energy corporation, led by the ruthless CEO Vesper, to retrieve the "Genesis Drive," a device rumored to hold the key to limitless clean energy, hidden deep within the most inaccessible part of The Gorge.

On his descent into the hazardous zone, Jax unexpectedly encounters Lian (Anya Taylor-Joy), a mysterious, highly skilled survivalist who has lived off the grid within The Gorge her entire life. Lian possesses intimate knowledge of the dangerous terrain, the unpredictable weather patterns, and the territorial, genetically modified creatures that inhabit the wilderness.

Lian initially views Jax with extreme suspicion, seeing him as another agent of the outside world trying to exploit The Gorge. However, their goals align when they realize the Genesis Drive is not merely an energy source, but a highly unstable weapon Vesper intends to use to enforce global control, rather than provide clean power.

The two form an uneasy partnership. Their journey forces Jax to confront his reliance on technology, which constantly malfunctions in the Gorge's electromagnetic disturbances, and rely instead on Lian’s instinct and primitive skills. The danger is twofold: the environmental hazards and the heavily armed retrieval teams Vesper sends after them.

The climax is a brutal fight set on the edge of the deepest ravine of The Gorge. Jax and Lian manage to retrieve the Genesis Drive, but they are cornered by Vesper’s elite squad. The final confrontation pits Jax's tactical military training against Lian’s raw, environmental survival skills. They decide that the drive is too dangerous for anyone to possess.

The film concludes with Jax and Lian destroying the Genesis Drive, neutralizing the threat posed by Vesper, and frustrating the corporation’s plan. Jax chooses to abandon the metropolis life, finding purpose and redemption by remaining in The Gorge with Lian, dedicating himself to protecting the dangerous, untamed world they now call home.