After a traumatic, life-changing assault, Kate Cassidy is visited by the Morrigan, the Celtic raven goddess of war and death. Gifted with the power to change shape into a raven-as well as a shape halfway between human and bird-Kate ends up in Boston, tracking down her last attacker who escaped justice. There she discovers she's part of a world of Shadows: vampires, werewolves, demons, angels, wizards, and everything in between. When a Shadow begins committing murders-one of them her best friend-she realizes she must do something to stop it. Before the humans learn about the monsters that live among them.