When a massive explosion at a top-secret prison known as the Pit allows notorious serial killer Richard Harris to escape, disgraced FBI agent Bex Henderson is called back into action to hunt him down before he kills again.

Bex’s alliances are tested amidst an intense manhunt for Clayton Jessup, a deranged killer who targets happy families, and is on the loose and looking to kill again. Meanwhile, flashbacks to Bex’s past reveal why she chose this dangerous line of work.

The team travels to rural Montana to hunt down Lowe, a dangerous serial killer obsessed with wolves, but local rangers seeking their own form of vigilante justice prove to be formidable adversaries.

Dr. Ezekiel Malak, a hospital psychiatrist turned deranged killer, is prowling for new victims in Chicago, so Bex and the team work to find a method to his madness in a desperate bid to get ahead of him — until Malak makes a move no one saw coming.

When Bex and the team race to stop Roy Barber, known as the Couples Killer, before he strikes again, they uncover a chilling scheme that puts Roy's crimes in an entirely new light.