Michael Thomas is a scientist with the CDC in Atlanta. He is also a dedicated marathon runner and a serial killer. Michael tells us in great detail about killing twenty-six people over twenty-six years as part of his marathon running experiences in twenty-six US states. He also describes many marathon locations and events where he participated in races but did not murder anyone. Each murder is unique, and a wide variety of murder techniques are utilized to confuse the police and the FBI. A romantic relationship develops between the killer and Susan Harvey, the FBI agent assigned to solve the marathon murders case. Their ongoing affair adds complexity to the story and to the murder methodology. Michael slowly reveals himself to Agent Harvey as she gets closer to having the evidence she needs to arrest him. The story ends with a series of events that are both exciting and unexpected.