Spokane, Washington, a bustling city split by hurtling white-water falls. One afternoon a young woman's body is found buried in a riverside park - then a second body, then a third. Before the week is out Caroline Mabry is plunged into a full-blown hunt for a serial murderer her colleagues have nicknamed the Southbank Strangler. As Caroline and her troubled mentor, Alan Dupree, bridle under an investigation overrun by headline-grabbing "specialists" and bean-counting statisticians. As they close in on a suspect Caroline and Alan confront dark truths about the killer-hunting industry - and about their attraction to each other. And in the end they come face-to-face with an evil very different - and far more alarming - than the one they thought they were chasing.