Caine Soren, Sam’s fraternal twin and rival, wakes disoriented and weak in a cottage at Coates Academy located north of Perdido Beach. Diana Ladris, a girl with the ability to measure mutant power levels, brings him food and explains he has been delirious for three months, ever since a mutant coyote named Pack Leader led him to a mine shaft where he encountered an entity called the Darkness. During his illness, Caine killed a boy named Chunk by telekinetically throwing him through a wall, yelling the word “gaiaphage.” Caine pretends not to know what the word means. Diana has been caring for him because the alternative is dealing with Drake Merwin, a violent kid who has taken over in Caine’s absence and raided Perdido Beach for food. Bug, a boy with camouflage powers, has been spying on Perdido Beach and reports that Sam Temple controls the town and has several kids guarding the food supply. Caine announces he has a plan to gain leverage over Sam, who defeated and banished him three months earlier. He commands Diana to bring him Drake and Bug, and Diana warns him that Sam will not show him mercy a second time.

The scene shifts to Astrid Ellison in Perdido Beach. Sam arrives and tells her E.Z. is dead, killed by mutant worms. He gives her a dead worm to study. Astrid, the group’s de facto scientist nicknamed the “Genius,” photographs it and adds the images to a laptop folder documenting mutations. The worm has shark-like teeth and thousands of tiny leg-like structures that allow it to bore through flesh. The worms have developed unnaturally large brains, which indicates a collective intelligence and strict territoriality. Sam confesses his guilt and horror: When he cremated E.Z.’s body, the smell of burning flesh made him salivate from hunger. Astrid comforts him, then debates telling Sam about Little Pete’s disturbing new behaviors; her five-year-old brother with autism has been creating strange physical manifestations. Astrid decides against informing Sam and tells him Pete is fine.

Lana Arwen Lazar, known as the Healer, lives in isolation at the Clifftop Resort with her dog, Patrick. She discovered her healing power after surviving a crash on the day of the FAYZ. Only a few people know her location because she wants to retain some control over her life and avoid being constantly harassed for treatment. Food is scarce; the hotel has been cleared of everything but alcohol. Lana recalls being captured by a mutant coyote pack and driven into a mine shaft where she encountered a malevolent entity called the Darkness. The memory triggers a menacing voice in her head—the Darkness itself—telling her to come to it. The voice has grown increasingly insistent over time.

The narrative shifts to Mary Terrafino, who runs the day care. She compulsively weighs herself: She is down to 81 pounds from 128 but still sees herself as overweight. She takes Prozac and appetite suppressants and skips breakfast, revealing her eating disorder. At the day care, her brother John lists the morning’s minor crises. A boy named Francis arrives for his mandatory work shift, complaining bitterly. Mary reflects on the phenomenon called “Stepping Out,” where kids vanish on their fifteenth birthday after being presented with a choice to leave or stay in the FAYZ. A vision of a loved one, masking a hidden monster, beckons them to a light, though no one knows where they end up if they choose to follow. Two five-year-olds who have aged out of the day care arrive in tears, and despite the rules, Mary allows them to stay.

Drake Merwin occupies the school’s psychologist’s office in the damaged Coates Academy, turning the room into an armory with his collection of guns. He has a whip-like tentacle where his arm was burned off by Sam; the Darkness had given Drake this mutation when he accompanied Caine down in the mine. Diana tells him Caine wants to see him, and he reluctantly reports in.

In Caine’s cottage, Bug is also present, nearly invisible due to his camouflage power. Caine reveals his plan to take control of the nuclear power plant from Sam, thereby controlling Perdido Beach’s electricity. He sends Bug to scout it. After Bug and Diana leave, Drake tells Caine he doesn’t trust Diana. He reveals that Computer Jack, a tech whiz who switched to Sam’s side in Perdido Beach, has developed super-strength despite Diana previously rating him as powerless, suggesting she is working against them. Caine, suspicious, orders Drake to have someone watch her.

The scene shifts to Duck Zhang, a sixth grader relaxing in a private pool. Three older boys—Zil Sperry, Hank, and Antoine—arrive and begin bullying him. In a surge of rage, Duck’s latent power manifests; he becomes incredibly dense and sinks through the bottom of the pool, falling through solid earth beneath. The draining pool creates a dangerous whirlpool, and the three bullies barely escape. Humiliated and frightened, Zil reframes the incident, declaring to his friends that Duck is a “mutant freak” who tried to kill them, stoking anti-mutant sentiment.

Brianna, nicknamed the Breeze for her super-speed, tests whether she can outrun a bullet fired by Computer Jack. She is fast enough to dodge it but not to beat it outright. Both hungry, they share the last of a can of pizza sauce. Jack explains he has repaired the cell phone network, but Sam has not yet approved activating it because the Coates kids would also gain access. Brianna, remembering the abuse she suffered at Coates under Drake, angrily declares she wants the Coates kids to suffer and die. She storms off, leaving Jack behind.

The narrative shifts to Duck Zhang, who awakens in a dark cave at the bottom of the shaft created by his fall. He follows a faint breeze through a tunnel. After bumping his head, he becomes angry and his power activates again, causing his feet to sink into the ground. He realizes he is a mutant and that his power is tied to his emotions. He sees a faint, sickly glow ahead from a side passage, which he identifies as radiation. He recalls the meteorite that struck the town’s nuclear power plant 13 years earlier and the false assurance that the radioactive fallout had been contained. Duck avoids the light and instead follows the sound of water into complete darkness.

Sam, Albert, and Astrid arrive at the church for a town meeting about the food crisis. Only about 80 of the expected 250 kids show up. Oblivious to Mary’s eating disorder, Sam thinks her weight loss makes her look good and “model thin” (71). Sam announces E.Z.’s death and explains the food supply will last only about a week. Zil Sperry suggests attacking Coates to reclaim stolen food, but Sam rejects this as too risky. Howard Bassem raises the issue of the dangerous worms, and Astrid explains they are mutations with unusually large brains that enable territorial behavior. Howard dubs them zekes and suggests that Orc, a boy whose body is mostly made of rock, could harvest the cabbage field unharmed. Howard demands a case of beer per day as payment. Despite Astrid’s objections to enabling Orc’s drinking, Sam agrees to have Albert negotiate. Sam announces a new mandatory rule: Everyone age seven or older must work three days per week in the fields. The kids respond with blank stares and indifference. Frustrated and weary, Sam pleads with them to show up for work buses the next morning.

Drake and Bug are driven partway to the power plant, then hike the remaining distance to avoid detection. Drake warns Bug to avoid the road in case of infrared cameras and threatens to torture him with his tentacle if he fails. Once out of sight, Bug turns invisible and uses the road anyway. He reaches the power plant’s perimeter fence, digs underneath it, and enters, planning to search for food before conducting reconnaissance.

The scene shifts to Sam, lying in bed unable to sleep due to hunger and stress. He worries about the community’s breakdown: kids living alone, fires, accidental poisonings, and general disorder. Taylor, a girl with teleporting abilities, appears in his room and reports that a boy named Tom O’Dell was seriously injured when a girl named Sandy hit him with a bowling ball. The fight started because Tom had killed and was cooking Sandy’s cat to eat. Sam gets dressed to deal with the crisis.

Orsay Pettijohn, a girl who can enter people’s dreams, watches Drake and Bug from her hiding spot. She has been living alone in the national park since the FAYZ began, when her park ranger father vanished. For months before that, she had suffered uncontrolled psychic visions of strangers’ dreams. The constant visions stopped when the FAYZ came, bringing her mental quiet, and she later discovered her power now only worked on people sleeping nearby. She once followed a group of kids and was pulled into their dreams, including a frighteningly powerful dream from Little Pete, who warned her of a monster and a dark presence connected to the word “gaiaphage.” Now, out of food, she has come down from the forest. She enters Drake’s dream, which is filled with violent and perverse imagery, then crawls away to break the connection—but Drake awakens and captures her with his whip arm, knowing she was in his mind.

The narrative shifts to Duck Zhang in the dark cave. He determines he is in a sea cave and hears rustling from above. After fitful sleep, he wakes to find the cave lit by a dim glow from a submerged entrance and sees thousands of blue, yellow-eyed bats on the ceiling. The bats suddenly swarm him. He dives into the water to escape, but the bats follow, swimming with flipper-like wings. Desperate for air, he swims frantically until he breaks the surface in the open ocean and heads toward the beach.

Sam finds the work buses nearly empty; only about 15 kids have shown up. He and Astrid argue about how to motivate people and the younger children’s need for a parental figure. During their conversation, Little Pete begins to levitate. A nesting doll materializes before him and transforms into a monstrous creature with talons and teeth. Little Pete appears to be fighting the creature with his mind, causing its growing arms to wither. Astrid slaps Pete, breaking his concentration. The creature vanishes, and Pete falls. Astrid admits this has happened before, but she kept it from Sam. They realize something is powerful enough to fight Little Pete. Sam orders Edilio to take the bus and conscript workers door-to-door. Only Sam, Astrid, and Edilio know about Little Pete’s extraordinary powers and that he was the one who unintentionally created the FAYZ; Little Pete had prevented a nuclear meltdown by manifesting a barrier and, in his panic, inadvertently vanishing anyone 15 and older from inside the dome. The three keep this knowledge a secret to protect Little Pete.

The scene shifts to Albert driving to the cabbage field with Howard and Orc. At the field, Orc enters and is swarmed by worms, which only tickle his stone skin. Albert sets a work rate of one beer per one hundred cabbages. After two hours, a single worm attacks the remaining patch of human flesh on Orc’s face. Orc and Howard cannot pull it free. Albert yells for Orc to bite the worm, then punches Orc’s jaw, causing him to bite off the worm’s head. Orc is left with a bleeding hole in his cheek, and Albert injures his hand.

Drake brings Orsay to Caine, Diana, and Bug in the Coates dining hall. Without real food, some of the children have started eating boiled grass. Having seen Diana in Drake’s violent dreams, Orsay looks at her with a mixture of fear and pity that Diana finds unsettling. Diana reads Orsay’s power level as three bars (Sam and Caine are the only ones rated as four bars, the highest known apart from Little Pete). Orsay explains she can see the dreams of people within roughly 200 feet. Drake objects to having a mind-reader present and claims her as his prisoner, threatening to kill and eat her. He challenges Caine’s authority. Caine explodes with rage, asserting his dominance and alluding to his time with the Darkness. He unleashes his telekinetic power, causing the floor to erupt in a geyser of debris, then threatens Orsay into total obedience, saying he will give her to Drake if she ever disobeys.

The scene shifts to Lana preparing for her daily walk with Patrick. The Darkness speaks in her head, telling her to come to it. Albert and Howard interrupt her walk, bringing the injured Orc. Lana heals the hole in his cheek, ensuring it remains human skin. Orc weeps and reveals his real name is Charles Merriman. Lana confronts Albert for paying Orc with beer, but Albert defends his actions, explaining his theory that kids need incentives to work and outlining a plan for a new economy. Impressed, Lana praises his foresight and heals his injured hand. She asks if gold would work as currency; Albert invites her to his new club to discuss it. Lana agrees, her resolve to act against the Darkness bolstered by Albert’s example of proactive planning.