Mercy Thompson is a walker, a last-of-her-kind being who transforms magically into a coyote. Living between the dark world of werewolves, vampires, and fae and the daylight world of humans, she walks her own solitary path, seeking only peace. But now everything she loves is under attack by a baffling conspiracy. Friends have been kidnapped, captured, and killed. Out-numbered, out-muscled and out of time, there is just one thing Mercy knows for certain. She is going to stop them.