Hunting monsters was supposed to be the hard part. When Joy came to Apex City, all she cared about was protecting the Cits from the dangers lurking outside protective barriers. She understood the need for the secrecy surrounding her Hunts—no need to cause a panic by announcing just how real of a threat the Othersiders pose.

But as she quickly discovered, the conspiracies of the city run much deeper. And a dangerous new covert mission leaves Joy with a target on her back once more. Under the orders of her uncle, the city's prefect, Joy begins patrolling the abandoned tunnels and storm sewers under Apex Center. With her large pack of magical hounds, she can fight the monsters breaking through the barriers with the strength of three hunters.

Then she starts finding bodies. Psimons are turning up dead in the bowels of the city with no apparent injury. Reporting the incidents makes Joy the uncomfortable object of PsiCorps' scrutiny, and the organization appears more interested in keeping her quiet than investigating. Joy's situation grows more precarious, and her relationship with her Psimon boyfriend, Josh, begins to fray. Long-held tensions between PsiCorps and the Hunters seem to be reaching a breaking point.

While infighting threatens the stability of Apex City, Othersider forces are gaining strength and momentum outside the borders. Joy desperately seeks answers to figure out who her real enemies are before she and everyone she cares about are locked into an all-out war.