The Beast Must Die is a 1974 British horror film directed by Paul Annett. The screenplay was written by Michael Winder, based on the short story "There Shall Be No Darkness" by James Blish, which was originally published in Thrilling Wonder Stories. The film stars Calvin Lockhart, Peter Cushing, Marlene Clark, Charles Gray, Anton Diffring, Ciaran Madden, Tom Chadbon, and Michael Gambon. A millionaire big game hunter gathers six people at his remote English mansion, announcing that he suspects one of them is a werewolf. The viewer is invited to unfold the mystery along with the characters. Near the end, there is a 30-second pause called the "werewolf break", where the audience is asked to guess the werewolf's identity, based on clues from the movie. An alternative version of the film was released under the title Black Werewolf. This cut omits the "werewolf break" near the climax. Plot summary Millionaire Tom Newcliffe (Calvin Lockhart) invites a group of people, along with his wife Caroline (Marlene Clark), to spend some time in his rural English mansion, where he reveals that one of them is a werewolf and therefore must be killed. The group is composed of disgraced diplomat Arthur Bennington (Charles Gray); Jan and Davina Gilmore (Michael Gambon and Ciaran Madden), a pianist and his ex-student, now his wife; Paul Foote (Tom Chadbon), an artist recently released from prison; and Professor Lundgren (Peter Cushing), an archaeologist and a lycanthropy enthusiast. They all stay in the mansion where they are submitted to various tests to detect whether they might be a werewolf. The entire house is under surveillance by CCTV cameras, as well as motion sensors in the grounds around the mansion set up and overseen by Tom's associate Pavel (Anton Diffring), who does not believe in werewolves. The only way to determine the identity of the werewolf is for a certain combination of elements to occur all at once, including a full moon and the presence of wolfsbane pollen in the air. When this fails to produce any lycanthropic reactions, Tom makes each of the potential werewolves grab silver objects to provoke allergic reactions, but this too proves unsuccessful. Later that same night, Pavel is killed by the werewolf, which makes Tom even more obsessive in his hunt, to his wife's increasing annoyance. Tom gradually focuses his suspicions on Paul Foote, who was reportedly arrested after eating human flesh. Foote denies