After slaying a wendigo, banishing a sub-prince of Hell, and falling in love with Adrian Graves despite her addiction to demons, Vivianna Sky is on to her next adventure: locating and destroying the monstrous entity that plagues Munkai Island. The manananggal is attacking expectant mothers in the anachronistic village, resulting in the death of at least one child and the threat of many more lives.
Vivianna initially answers the call for the bounty on the manananggal's head, but once she lands on the island, everything changes. She feels a calling to kill the creature wreaking so much havoc, but the closer she gets to the case, the further Adrian seems to stray. Vivianna swears his eyes are drawn to Ilena Martin, the federal agent assigned to the island. And the distance between Adrian and Vivianna only widens when the Sky family curse rears its ugly head.
To kill the beast, Vivianna must give up everything—even and especially her own self-control. But will her loss of control destroy more than just the monster?