The party is almost over when the sky tears. Julietta, sitting with Emily on the porch, watches the sunset become a wound, two skies hanging impossible and terrible above Chicago. The incursion alarm blares, and before anyone can even name the disaster, Leviathans are crashing into the suburbs, Wasps are screaming overhead, and the Queen's domain is pressing against every unprotected body like a knife looking for a seam. Emily and Lia drag Julietta into a tiny car. Max crams himself into the trunk. Peter and Andre pile in, and then the car rolls after Julietta's first seizure. Max's corpse is pulled out of the trunk and Andre vomits. The survivors stagger through a shattered neighborhood, and Julietta's newborn power begins to answer her terror. When the Queen touches down, Andre lets go of her hand because he is panicking, and the invisible pressure turns him into a pile of cubed meat in an instant. Lia dies later because she is separated from Julietta during a fight. Emily alone survives by staying in contact, because Emily seems to know things she should not know. Julietta is impaled by a Behemoth, touches it, and becomes it. She kills the monster with her own stolen blade. She is not triumphant. She is naked, transformed, crying inside a body that belongs to a dead girl, and the only person left who knows her real name is a stranger who refuses to explain herself.

In the days that follow, Julietta learns what her power costs. She eats anything, steals the body of Emily's dead girlfriend Lia, and hides behind that name while Wasp acid tries to peel her away again. Emily guides them through impossible luck, leading them to Christine, a terrified girl whose power can take a house apart and hold it in the air like an exploded diagram. Then they find Anastasia, a nine year old blood witch who has killed Raptors with her own blood and watched her whole family fall apart. The four of them form a desperate pack. Julietta protects them by turning into Raptors and Wasps, but every transformation steals some of her brain, and every time she returns to a human shape she has to fight to remember who she is. Christine cannot use her power when it matters. Anastasia keeps cutting herself to fight. Emily keeps secrets. Behind them all, the Queen's pressure never rests, always whispering that they should be split into pieces. Their escape is a running battle through houses and backyards, with Julietta carrying them on her back as a monster while Anastasia bleeds to keep them alive. When an Angel tries to take Christine, Julietta eats the Angel's flesh, learns its body, and kills it with a stolen form. The next time she looks at her own face, she cannot say whether the hunger inside her belongs to the monster or to her.

The military finds them at the edge of the incursion zone. Agnus Dei burns a swarm of Angel clones, Cross Country teleports Julietta to a black site, and an interrogator with a truth detection power asks whether the girl in front of her is Lia Morgan. Julietta says yes in careful half truths. The power says she began existence four days ago. The soldiers shoot her three times. She apologizes through a Raptor brain, hides behind the name of a dead woman, and is drafted into a training camp for powered recruits. Commander's power can make anyone obey, and Julietta learns to fight her off by shrinking her domain. She is assigned a therapist who keeps notes on her, a roommate named Christine who cannot get out of bed, and a nine year old sister figure who wants to be a weapon. Peter, the foster brother who abandoned them, appears with powers of his own. He recognizes her, hugs her, and invites her to become a supervillain. She refuses. She is not allowed to run because Emily needs Lia's name to buy a combat exemption, and Anastasia needs a big sister who will keep her alive. The interrogation follows her into her dreams, leaving her to wonder if she is a copy of a copy, an Angel's power wearing a dead girl's skin, or just Julietta Monroe screaming in a body that was never hers.

Training continues and Julietta grows. She learns domains, range density, resonance and dissonance, all the arcane military vocabulary for the invisible pressure that now defines her life. She also learns how much she likes becoming. Commander sends her to a private zoo to collect new biological templates, and for a few hours Julietta is almost happy. Tigers, elephants, pangolins, penguins, creatures she never dreamed of become hers. She creates a nervous system distributed through her tentacles and eyes that bloom wherever she wants. Then the aquarium swallows her. Thousands of fish at once flood her domain and she stops being a person. She becomes a teeming mat of flesh at the bottom of a tank, unable to remember how to breathe, unable to make her own heart beat, sustained only by the octopus biology she has absorbed. Rebecca, the zookeeper, climbs into the water and holds her hand while she is not human anymore. When Julietta finally returns to something like herself, she realizes she has crossed a line. She has not only collected animal forms. She has learned to enjoy not being human, and that enjoyment is the most dangerous thing of all. The dream of falling toward the void grows stronger, and the Queen her Raptor brain longs for lies somewhere to the northeast, waiting for her to stop saying no.