Cass County, Minnesota: A sheriff's deputy steps out of a diner on a rainy summer evening, and a few minutes later, he's lying dead in the mud. When state investigator Kirk Stevens arrives on the scene, he discovers local authorities have taken into custody a single suspect: a hysterical young woman found sat beside the body, holdingthe deputy's own gun. She has no ID and speaks no English. The puzzle only deepens from there, as Stevens and Carla Windermere, his partner in the new joint state and FBI violent crime task force, find themselves on the trail of a massive international kidnapping and prostitution operation.