#1 New York Times bestselling author Patricia Briggs's Mercy Thompson series has been hailed as "one of the best" (Library Journal). Now Mercy must deal with an unwanted guest-one that brings a danger unlike anything she's ever known. When her mate's ex-wife storms back into their lives, Mercy knows something isn't right. Christy has the furthest thing from good intentions-she wants Adam back, and she's willing to do whatever it takes to get him, including turning the pack against Mercy. Mercy isn't about to step down without a fight, but there's a more dangerous threat circling. As the bodies start piling up, she must put her personal troubles aside to face a creature with the power to tear her whole world apart.