Dr. Warren Chapin (Vincent Price) has made a surprising discovery -- the spine-chilling sensation that people get when scared is due to a parasite that he dubs the "tingler." Chapin concludes that in extreme circumstances, prolonged fear can cause the creature to damage a person's spine and even cause death if the victim can't scream, a theory that Oliver Higgins (Philip Coolidge) uses to deadly effect on his wife (Judith Evelyn). Soon the tingler that killed the woman is on the loose.
Director: William Castle
Writer: Robb White
Producer: William Castle
Cast: Vincent Price, Judith Evelyn, Darryl Hickman, Patricia Cutts, Pamela Lincoln, Philip Coolidge, Gail Bonney and Pat Colby