Psycho Killer

Kansas Highway Patrol officer Jane Archer witnesses her husband, Mike, being murdered by a serial killer dubbed by the media as the "Satanic Slasher" due to the occult symbols left behind at the crime scenes. She becomes obsessed with tracking him down and bringing him to justice.

The Slasher is heavily implied to be a murderous Satanic preacher named Richard Joshua Reeves, who held his congregation hostage and then killed them, but he was said to have died in prison. The Slasher murders a female pharmacist in a small town and raids the pharmacy for a variety of antidepressants and other drugs, which he consumes in large quantities. Later, he murders two stranded motorists on a country road, before violently killing a Catholic priest and drinking his blood. Jane tracks the Slasher's killing spree, which began on the west coast, across the Midwest. During her travels, Jane discovers that she is pregnant with Mike's child.

In Nebraska, Jane finds the Slasher staying in a motel, where he attacks her before fleeing. The Slasher goes to a Satanist mansion run by a man named Mr. Pendleton. The Slasher uses Marvin, an assistant and adherent to Pendleton, to track down Leonard Wilkes, the manager of a nuclear power plant in Harrisburg, Pennsylvania. He then kills Pendleton and his followers, except for Marvin.

The Slasher's goal is ultimately revealed to be to destroy the Harrisburg plant operated by Leonard by self-detonating in a suicide mission to "open the gates of Hell" and appease Satan. Jane catches up to him and warns the other guards after he uses the man to get him into the control room to carry out his deed by setting off explosives. Jane breaks through the window of the control room and manages to incapacitate the Slasher by shooting him.

Jane is left traumatized from her ordeal, while the Slasher is revealed to be Reeves, who is brought to a prison in Death Valley, California, where his spree began.