Following the assassin of President John F. Kennedy, a suspicious outbreak of suicides, accidental deaths, and outright murders decimates assassination witnesses. When Nathan Heller and his son are nearly run down on a city street, the private detective wonders if he himself might be a loose end. Soon after Heller and celebrity columnist Flo Kilgore explore a growing list of dead witnesses and investigate the increasing wave of violence that seems to emanate from the notorious Mac Wallace, rumored to be LBJ's personal hatchet man.