Someone has murdered euthanasia champion Dr. Eldon Mate--a self-styled Dr. Death responsible for scores of assisted suicides. In a burst of bloody irony, the killer chooses to dispatch the doctor in the back of Mates own suicide van, hooking him up to the killing apparatus dubbed the Humanitron--and adding some butchering touches of his own. The case is assigned to veteran LAPD homicide detective Milo Sturgis, who turns, once again, to his friend Dr. Alex Delaware. But working this case raises a conflict of interest for Alex so profound that he cant even discuss it with Milo. The tension that develops between cop and psychologist further complicates an already baffling and complex murder investigation--one whose suspects include the families of Dr. Mates travelers, Mates own son, and a psychopathic killer who relishes the geometry of death.