The second installment in the Penryn & the End of Days series picks up immediately after
Angelfall. In a post-apocalyptic world devastated by an angel invasion, seventeen-year-old Penryn Young lies seemingly dead on her mother's lap in a Resistance truck fleeing the ruins of the angel aerie in San Francisco. Penryn was not killed but paralyzed by the sting of a scorpion-angel, one of the monstrous hybrid creatures engineered in the angels' laboratories. The last person to hold her was Raffe, an archangel whose feathered wings were severed by enemies and replaced with bat-like demon wings against his will.
When Penryn sits up, the refugees panic until Dee and Dum, twin Resistance operatives, defuse the situation with dark humor. Her seven-year-old sister Paige sits nearby, her body covered in crude stitches and her teeth replaced with razor-edged metal grafts from angel experiments. The caravan reaches Palo Alto High School, the Resistance's new headquarters. Paige cannot keep down food, and Penryn hides Raffe's angel sword under her blanket.
A surveillance feed captures Beliel, the demon who stole Raffe's wings, limping across the San Francisco airport, pursued by a demon-winged figure: Raffe, alive and hunting his enemy. Obi, the Resistance leader, orders a capture team, but the mission redirects when scouts report angels gathering at the old aerie. There, the team watches warriors revive buried comrades with water as angels riddled with bullets shake off their injuries and fly away. Penryn realizes the Resistance's successful strike was largely luck, since most warriors had been absent during the attack. From the rubble emerges Clara, a woman Penryn freed from a scorpion tank during the raid, her body drained nearly dry by the fetus that fed on her.
Back at school, Paige has not eaten in three days, though she gulps at the mention of raw meat. Penryn begins experiencing vivid dreams through the sword, which is partially sentient. It replays Raffe's memories in slow motion, teaching her combat techniques as she mimics his fighting stances against hellions, bat-faced demons, across centuries of history. She disguises the sword with a teddy bear and bridal veil to make it unrecognizable, but when she tries hunting a squirrel for Paige, the sword interrupts with visions of Raffe leading angel armies, as if offended at being used for such a mundane task.
Three armed men attack Penryn for her sword, but Paige crashes into them in a feral blur, slashing one and stalking the others on all fours. Spectators witness Paige's monstrous capabilities. Afterward, the sword shares the memory of Raffe's wing amputation: the agony, a human girl (whom angels call a Daughter of Man) throwing the sword to him so he could fight back, and his last thought that his Watchers, angels condemned for marrying human women, would have liked this girl.
Later, Penryn finds Paige tied up by Resistance members in the grove. The body of one of her attackers lies nearby with chunks missing. Paige licks blood from her lips, and Penryn hesitates, her sister reading the judgment in her eyes. A swarm of mature scorpion-angels descends on the camp. Paige flees into the trees, their mother chases after her, and Penryn fights off scorpions using techniques from her dreams. Obi locks Penryn in a police car with her mother, who screams that Penryn let the monsters take Paige before collapsing into sobs. Clara helps them escape with a key the twins secretly dropped, and Penryn's mother reveals a prototype pet tracker with transmitter chips sewn into the girls' clothing. The tracker shows Paige heading toward San Francisco.
They follow the signal to the waterfront, where Paige's tracker points to Alcatraz Island, now swarming with scorpions. On the pier, Beliel flushes out hiding humans with nets. Raffe attacks him but Beliel escapes. Penryn frees the trapped prisoners with her sword, but new scorpions arrive and she, her mother, and Clara are captured and ferried to Alcatraz.
The island holds a cavernous underground factory where rows of water droplets suspended from the ceiling each contain a human in fetal position, progressively transforming into scorpion-angels. When guards try to feed Penryn and two fellow prisoners to the creatures, the men fight back and escape to an office, where they meet Doc, a human scientist running the factory. Doc proposes an escape plan and shows Penryn surveillance video of Paige's captivity with Beliel. The footage reveals him tormenting the child, calling her Little Worm, yet eventually protecting her and asking her to sing him to sleep before discarding her to the surgical team. Doc reveals that Paige's stiff movements reflect constant pain from surgeries performed without painkillers. He confesses that he secretly altered Paige's batch of experimental children using stolen angel science, hoping to give humanity a survival advantage. Paige is the only altered child who survived.
Penryn is smuggled to the new aerie at Half Moon Bay, a luxury hotel on coastal bluffs, where she serves as one of Uriel's matched trophy girls. Uriel, the archangel who orchestrated Raffe's wing switch, is campaigning to be elected Messenger, the angels' supreme leader. He engineers a masquerade party to tempt warriors into breaking their taboo against relations with human women. At the party, Penryn spots Raffe among the disguised angels and trips into Uriel to create a distraction, allowing Raffe to slip away. Uriel then declares that biblical locusts have emerged from the Pit, presenting his scorpion creations as confirmation of Judgment Day. The swarm darkens the sky, warriors erupt in bloodlust, and the violence becomes a massacre Uriel cannot control.
Raffe finds Penryn in the carnage and flies her out over the ocean. After an aerial fight with pursuing angels, Penryn falls into the freezing water, fends off a drowning angel with a knife, and swims to Raffe, who cannot swim. She tows him to shore. In a beachfront house, they share a quiet respite. Raffe explains that angel society enforces strict rules and a relationship between them is forbidden. The true punishment for warriors is not death but losing the people they care about.
Flying over the bay, they spot boats carrying the Alcatraz escapees, confirming the prison break succeeded. At Pier 39, Penryn finds Clara reunited with her family. Penryn retrieves her sword and the tracker, which shows Paige at the aerie. Raffe reluctantly agrees to fly Penryn there despite the danger.
At the aerie, the scorpion swarm returns and Paige walks stiffly out of the darkness toward Beliel. She takes his hand, then leaps and tears into his neck while scorpions pump him with venom. Raffe severs both stolen wings from the paralyzed Beliel. When the angel Burnt, who originally kidnapped Paige, reaches for her sister, Penryn draws her sword and fights him using the techniques the sword taught her. The sword channels its own fury at the angel responsible for separating it from Raffe. Burnt's blade shatters, and Penryn's stroke cuts through his chest. Every unsheathed angel sword in the area drops from its wielder's hands, the archangel sword having intimidated them into submission.
The scorpion swarm crashes into the advancing angels, flattening everyone except Penryn, Raffe, and Paige, around whom the swarm splits protectively. Whatever Doc did to Paige has given her a connection to the creatures. Penryn retrieves both severed wings and reunites with her sister. Looking into Paige's eyes, she finally sees what her mother always told her to see: the same brown eyes, full of sweetness and light. Paige climbs onto Beliel's shriveled body, pressing Raffe's wings against his back, and scorpions lift them into the air. Raffe grabs Penryn and leaps off the cliff, joining the swarm as it blocks the pursuing angels. They fly together as the sun rises over the ocean, bringing a new day in the World After.