When a young woman is found dead at the bottom of a boat in the Castlemere Canal, completely naked, and full of crack cocaine, the inhabitants of the dockside town are shocked. How could such a thing happen in Castlemere? The town's trio of police, detectives Frank Shapiro, Liz Graham and Cal Donovan, are concerned with answering a more basic set of questions: Who is this woman? How did she get on that boat? Why?

The detectives quickly determine that she was thrown off the roof of a local hotel -- where an international business convention was being held, complicating the list of suspects. Suddenly, the deaths of a sheep from a local farm and of a homeless man throw the case off course -- someone in Castlemere is using live objects for target practice. Shapiro finds out firsthand that there is a professional killer on the loose, leaving Graham and Donovan to try and piece this puzzling case together alone.

When a panicky phone call from a friend of the dead woman offers to shed light on these bizarre events Liz sends Donovan to fetch her. It should take only a few hours, but even that may be too long...