When Bryce returns to her and Danika's apartment from a date with her human boyfriend (he's not important to the novel at all), she finds that Danika and the entire Pack of Devils have been slaughtered in her apartment. Upon leaving the crime scene, Bryce finds an angel who is being attacked by a demon. She fends off the demon and calls for help, but she suffers a significant injury to her thigh. After Danika's death, Bryce is worried that Danika will not be deemed worthy for the Bone Quarter because she heard a recording in which it sounded like Danika begged her assailant for mercy. For this reason, Bryce makes a deal with the Under-King to trade her place in the Bone Quarter for Danika's. After the Pack of Devils' death, Bryce stops drinking and partying, and she experiences a major depression in which she considers taking her life, although she is saved by her friend Juniper.

The book fast forwards two years to a business deal that Bryce is coordinating between Jesiba Roga and Maximus Tertian. The same night after Maximus and Bryce meet, Maximus is found slaughtered in the same way the Pack of Devils was. After this incident, the Governor, Micah, assigns Bryce to the case to discover who, or what, is killing the city's residents. Micah also assigns his personal assassin, Hunt Athalar, to protect Bryce. From here, Bryce and Athalar slowly become friends as Hunt comes to realize he had made incorrect assumptions about Bryce. Like many, he had assumed she was an ignorant party girl, but he soon discovers that Bryce uses this assumption about her to her advantage as she maneuvers and outwits people.

At one point during the investigation, Micah convinces the entire investigation team that Danika Fendyr was addicted to Synth, a powerful drug that gave the Vanir immense strength but simultaneously drove them to kill everything in their path, including themselves. Micah reasons that Danika took Synth the night of her death, and then she killed the Pack of Devils and herself. Bryce eventually comes to believe this version of the story.

Shortly after Bryce accepts Micah's version of events, a Summit takes place for Valbaran leaders. During the Summit, all the city heads and important city officials are out of town. While Bryce is working, Micah leaves the Summit and confronts Bryce at her workplace because he believes she has Luna's Horn inked on her back. After sending his power into Bryce, he uses Luna's Horn to open a portal to Hel. During this confrontation, Bryce kills Micah.

During the invasion of Lunathion by demons, Bryce goes to Asphodel Meadows to protect the humans, where she demonstrates her skill with firearms. She then goes to the Heart Gate in the center of the Old Square with a plan to close the portals. After making the Drop, she uses her Starborn powers and Luna's Horn to channel her light into the portals and seal them.

When back at her apartment, Bryce receives a call from Rigelus, the head of the Asteri. He warns her to lay low and threatens to harm her family if she doesn't. As a "gift," he also frees Hunt from enslavement.