Kenneth Magee (Desi Arnaz, Jr.) is a young writer who bets his publisher (Richard Todd) $20,000 that he can write a novel as good as Wuthering Heights in 24 hours. To prepare, he goes to a deserted Welsh manor house called Billyddpaetwr Manor. He was told it was empty, but he finds Lord Grisbane (John Carradine) living there with his daughter Victoria (Sheila Keith). It is a dark and stormy night and other people show up—Lord Grisbane’s sons Lionel (Vincent Price) and Sebastian (Peter Cushing). Also, Magee’s publisher’s secretary Mary Norton (Julie Peasgood) and a potential buyer for the property named Corrigan (Christopher Lee).
The Grisbane’s reveal that they are there to release their brother Roderick (also Christopher Lee) who has been imprisoned in a room for forty years for seducing a young village girl and murdering her when he learned she was pregnant. But entering the room, they find him gone and assume that he had broken out. Suddenly, Lord Grisbane has a heart attack. They hear screams and find Victoria strangled to death. Those who try to leave the manor find their tires slashed.
A young couple that Magee met at the station—Diana (Louise English) and Andrew Caulder (Richard Hunter)—arrive seeking shelter from the storm. Diane washes her face with water that has been replaced with acid and Andrew drinks poisoned punch. The rest decide to find Roderick and kill him before he finishes them all off.
Magee, Sebastian, and Mary explore tunnels discovered behind a bookcase. They are separated and Sebastian is hanged from the ceiling. Mary gets out safely but Magee is still lost in the tunnels. Corrigan reveals that he is Roderick and escaped his prison decades ago but returns now and then to make his family believe he is still locked up. He kills Lionel with a battle axe and chases Mary around the manor. Magee finds them and knocks Roderick down the stairs. Roderick accidentally stabs himself with the axe. As he is dying, his victims walk into the room, quite alive, and then Roderick gets up. It was all a joke on the part of Magee’s publisher. This was in fact Magee’s story. He gives it to his publisher, who gives him the money, and then he rips up the check because he has learned that some things are more important than money.
The film was directed by Peter Walker and produced by Menachem Golan and Yoram Globus, from a script by Michael Armstrong, based on the 1913 novel Seven Keys to Baldpate by Earl Derr Biggers, which had already been made into several plays and films. It is remarkable because Price, Lee, Cushing, and Carradine are in it together. They are all great to watch and the film isn’t bad until you get to the story-cheat ending which disappointed audiences and enraged critics. The original play by George M. Cohan opened 22 September 1913 and ran for 320 performances. This was the last of 24 films in which Christopher Lee and Peter Cushing appeared together. Peter Cushing killed Christopher Lee in six films, but this is the only one in which Christopher Lee kills Peter Cushing.
Vincent Price does not appear until 40 minutes into the film. John Carradine fell asleep during the dinner scene. It is often pointed out that Vincent Price and Christopher Lee were both born on May 27 and Peter Cushing on May 26. I can add that all three of these sweet and charming gentlemen who have made a career of pretending to be evil monsters were born with the sun at five degrees of Gemini. And Basil Rathbone’s birthday, incidentally, is a week later. Despite the stagy cheat ending, the story is fairly gripping, the atmosphere creepy, and Lee, Price, Cushing and Carradine are in some pretty long scenes together, acting up a storm. That doesn’t always happen.