The shooting death of a Panamanian horse jockey puts Detectives Fontana and Falco on the track of a pack of colorful suspects who inhabit the competitive racing world, forcing them to nudge jockeys, trainers, and even a rich owner; to discover who would murder the rider over his desire to ride one particular horse. However, their probe reveals that the victim challenged the registry and selling details of the prized three-year-old, leading the cops and EADA McCoy to a corporate head who bought the thoroughbred with stolen funds.

A commuter train is violently derailed when it strikes an SUV parked on the tracks, resulting in 12 deaths, leaving Detectives Fontana and Falco sifting through massive debris, until they lock onto a depressed construction worker who maintains he only intended to commit suicide, not homicide. EADA McCoy cannot wait to get his hands on the case but his grip gets more slippery when the accused's attorney hints at an insanity defense, and the suspect later shocks everyone in court.