The wager

Captain Tom Mason of Homicide has a peculiarly horrible case to deal with. He investigates a murder where the victim has been decapitated. However, only the body remains at the crime scene. The murderer appears to have taken the head as a grisly trophy. Prompt police action, as they cordon off the area, yields four suspects. One of them, identified as running from the scene, is held in custody - but then another three people are decapitated ...