https://www.youtube.com/watch?v=amZGPxmGxxQ
Based on a James Blish short story, The Beast Must Die (1974) is a curious twist on the Clue genre: A millionaire invites a group of people to a remote island and reveals that one of them is a werewolf, and they must work out who it is.
The movie includes a 30-second “werewolf break” near the end, in which the audience are asked to guess the werewolf’s identity based on the clues.