In the 1930s, Larry Abbot and Vickie Pearle are performers on a hit
radio show,
Manhattan Mystery Theater, who are about to be married. Over the previous few weeks, Larry has been plagued by stammering and forgetting his lines, as well as a constant sense of fear, which has affected the show's ratings. In frustration, the show's sponsor and producers contact Larry's uncle, Dr. Paul Abbot, a noted psychologist. Paul believes that Larry's imminent wedding has disturbed something in his psyche that is frightening him, and decides to treat him by giving him a stronger fright, similarly to scaring away someone's
hiccups. Larry and Vickie travel to the castle-like mansion in which Larry grew up, now owned by his great-aunt Kate, to stay the weekend with Larry's family, leading up to their wedding. The other guests are Larry's uncles, Paul and Francis Sr., who is also Kate's lawyer; Larry's cousins Charles, Nora, and Susan; Larry's old girlfriend Sylvia, who is now dating Charles; and Susan's magician husband, Montego the Magnificent. Also present are the butler, Pfister, and his wife Rachel, the maid. Larry's final cousin, Francis Jr., was expected for the weekend but has disappeared. That night, a
hit man disguised as a werewolf is killed by the person who hired him to kill Larry. The hit man instead killed Francis Jr., having mistaken him for Kate. The killer attempts to stab Larry but is thwarted when Larry discovers Francis Jr.'s body in his bed. The killer quickly removes the body before Larry can return with Pfister, making Larry begin to doubt his sanity, especially when he then sees a deformed man walking down his wall and a ghostly apparition of Vickie. Larry and Pfister find Francis Jr.'s body in the cellar. The killer, now donning the werewolf disguise, attacks Larry, reminding Pfister of Kate's earlier claim that one of her family members is a werewolf. Larry escapes, and Pfister discovers the hit man's body beneath Francis Jr.'s. The two try to bury the bodies, fearing Larry will be framed for the murders. The murderer attacks them but is seen by Kate, who leads the family to find the dead bodies. They recover Pfister, but the murderer has already buried Larry alive in a glass coffin. While trapped, Larry has a
flashback and realizes that his recent fears stem from a repressed memory of his mother being killed by a thunderstorm during her wedding. Meanwhile, Vickie realizes Charles is the murderer when he pretends to talk into a disconnected phone. Charles attacks her, but she flees and is joined by Larry, who has been freed by Kate and her dog. Charles and Larry struggle, but Kate arrives and shoots Charles to save Larry and Vickie. ==Cast==