At the plaza, Zil decides only participants in Hunter’s execution will receive meat, believing this will bind them permanently to the Human Crew. Lance proposes hanging Hunter from the ruined church arch. Astrid arrives and confronts Zil, invoking God and conscience. Zil counters that there are no parents or God in the FAYZ and accuses Astrid of being a “freak-lover” and wasting her time nurturing a brother with a disability. When Astrid shows fear, Hank strikes Little Pete unconscious, and Zil orders Astrid seized.

Near the power plant, Caine’s group finds the fuel rod amid a small brush fire and rests briefly. When Drake arrives claiming to have defeated Sam—his tentacle ending in a stump from Brianna’s attack—they prepare to drive to the mine.

At the ghost town, Dekka struggles to stop Edilio’s bleeding. He urges her to collapse the mine, but she refuses because only Lana can save him. As Dekka drags Edilio away, coyotes surround them.

Duck floats high above town and spots Brianna below. She tells him Sam needs him and shares raw bird meat, then instructs Duck to reduce his density to 10 pounds and climb on her back for transport.

Sam, in excruciating pain as the morphine wears off, signals Quinn, who is searching from his boat, with a pillar of green light from his hands. Quinn arrives and wants to take Sam to town, but Sam demands a car to pursue Caine.

Near the ghost town, a new Pack Leader declares his coyotes will eat Edilio. When three coyotes attack, Dekka levitates them along with Edilio. Caine’s group arrives. Drake chases Dekka up the mine trail while Caine pilots the fuel rod overhead. Drake’s tentacle is visibly regenerating. Dekka throws Drake into the air with her power but cannot escape the coyotes, who attack from all sides and pin her down.

Drake taunts the pinned Dekka about the uselessness of mutant powers. Jack, sickened by the violence, throws two coyotes and kicks a third so hard its head tears off. The remaining coyotes flee. Drake wraps his whip around Jack’s throat, but Jack easily pries it loose. Drake tells him to back up his plan and offers Brianna as a prize.

Inside the mine, the gaiaphage floods Lana’s mind with its plan to combine Little Pete’s, whom he refers to as “Nemesis,” imagination with her healing power and uranium fuel to create layered, regenerating monsters and become unkillable. When she realizes she shot Edilio, rage briefly disrupts the gaiaphage’s control before it reasserts dominance.

At the mine entrance, Caine struggles with exhaustion. Diana warns him Drake will betray him. As Caine prepares to throw the fuel rod into the shaft, Diana screams at Drake, calling him “psychotic” and “filthy.” Drake’s whip lashes out at her.

Drake’s whip strikes Diana twice, smashing her head against a rock. The fuel rod crashes near the mine entrance, bending and cracking. Jack screams about radiation as his dosimeter wails. Drake charges Caine, firing his gun. Sam and Quinn arrive, and Sam’s light blast melts Drake’s gun barrel. Caine throws Sam backward, claiming Drake as his own target.

Caine immobilizes Drake with telekinesis and hurls the fuel rod at him. Both tumble into the mine shaft. The gaiaphage attacks Caine’s mind with psychic pain. Declaring his autonomy, Caine pulls everything back out of the shaft—debris, the truck, Hermit Jim’s body, the fuel rod, and the wounded Drake—and hurls it all back down in a spinning mass. The mine collapses completely.

Caine finds Diana barely breathing. When Sam approaches, Caine tells him to kill him if he wants. Sam reveals their plan: Duck will drill a rescue tunnel to recover Lana. Brianna arrives, towing the floating Duck.

At the plaza, Orc intervenes in the execution riot, throwing Zil through the air and declaring no one hurts Astrid. Howard appears at his side, and they disperse the mob.

Inside the collapsed mine, Lana watches the gaiaphage consume the spilled uranium. Her mind briefly clears as the creature feeds, and she realizes her only hope is to die from radiation poisoning before the gaiaphage forces her to heal herself.

On the hillside, Duck increases his density and falls through the ground, creating a vertical shaft into the mine tunnel. Caine descends, then lowers Sam. They find uranium pellets scattered everywhere.

They enter a vast cavern where a meteor struck years ago. The walls appear melted and resolidified. Caine lifts Sam’s hands to increase the light, revealing a mass of green crystals with a mirrored surface. Speaking through Lana, the entity identifies itself as the gaiaphage. Caine throws the fuel rod at the creature, but it bounces off harmlessly. As Sam collapses and the gaiaphage attacks Caine’s mind, Duck repeatedly yells for Caine to throw him. Caine hurls Duck, who transforms to maximum density and drills through both the gaiaphage and the cavern floor, creating a vortex that pulls the creature down with him.

As Duck falls through the earth with the gaiaphage’s crystals choking him, he has flashes of childhood memories. His final thought is that he did want to be a hero. Duck stops falling into the earth’s depths and dies.

Quinn descends the shaft Duck created and finds Caine, the unconscious Sam, and Lana standing amid the wreckage. Lana asks if she is alive and free. When she begins to leave, Quinn stops her, saying they need the Healer. She protests that she killed Edilio, but Quinn replies that Edilio is not dead yet.

At the day care, Mary wakes tied to a chair. Her brother John angrily force-feeds her fish, her eating disorder now exposed.

By sunrise, Lana has healed Diana, then Edilio, Dekka, Brianna, and finally Sam. Caine and Diana leave immediately. As Lana admits she cannot cure memories and begins to cry, a car arrives bringing Astrid and Patrick. Lana embraces her dog.

The next day, Edilio digs graves for Mickey Finch and Brittney. An 18-inch slug creature, Drake’s severed tentacle, attached to Brittney cannot be removed and is buried with her. A cross is erected for Duck, whose body cannot be recovered. Sam eulogizes Duck as a hero who willingly sacrificed himself. Afterward, Edilio paints over the Human Crew graffiti.

Sam listens to Albert explain a new gold-backed currency that Howard has nicknamed Albertos, and reflects on ongoing problems: Zil’s capture, anti-freak graffiti, Mary’s illness, and the permanent loss of electricity. Jack has rejoined the group and stands awkwardly near Brianna.

At the cabbage field, they test a new harvesting method using blue bats as bait to draw zekes away while Orc and Brianna safely retrieve cabbages. The plan succeeds. Hunter, whose execution was averted by the riot, was later tried and sentenced to exile; he now supplies the town with hunted game.

Sam, Astrid, Albert, Edilio, Dekka, Howard, and John Terrafino form a Temporary Council. They jokingly arrest Sam and sentence him to mandatory relaxation. They take him to the beach, where Dekka uses her gravity power from a boat to create a wave. Sam smiles and paddles out to surf.

The final scene reveals Brittney is conscious in her grave, unable to move and accompanied by Drake’s severed tentacle, mentally begging her deceased brother, Tanner, to pray for her.