She has never feared the walking dead. It's the power required to reanimate the dead that startles her, seduces her. The power that dwells inside her...and is growing.

For Professor Ruby Montagne, being a necromancer has brought her nothing but heartache, and she walked away from that part of her life long ago. However, her quiet existence in San Francisco is shattered when she stumbles upon the body of a slain witch, and the supernatural community insists she transform him into a revenant to track the killer. But his murder was just the beginning, and Ruby soon realizes that the stakes are higher than anyone can imagine—and that revenants have nasty minds of their own.

Now demonic creatures have escaped into the human world, and zombies once again walk the streets. For humanity's sake, Ruby forms an unlikely alliance with a witch, a revenant, and Ewan March, a demon warrior who sets her senses on fire. She's always distrusted demons, and Ewan is no exception. But circumstances push them closer together, and Ruby not only finds it harder to resist him, she isn't sure she even wants to.

But she suspects his job of patrolling the portal separating humans and demons conceals a dark and deadly past that may consume them both. With events spiraling out of control, Ruby unravels a plot that threatens the human and demon realms and puts Ruby's very soul in jeopardy. Because when the dead walk, no one is safe. Especially Ruby.