Around 1972, Robert Shaw expressed an interest in playing the lead in this movie. He was experiencing a lull in his career and faced some large bills. Don Sharp was the intended director at the time.
Jan Jarmokowski:
Smile your on Candid Camera!
Tom Newcliffe invites several people to his estate because he is convinced one of them is a werewolf and intends to identify and hunt the one who is. After dinner the first evening, he explains this to the gathered people. Newcliffe goes from one guest to the next, explaining how he suspects each of being a werewolf. However, he does NOT indicate that he has conclusively (or at least to his satisfaction) confirmed the existence of one werewolf and determined that its normal human form must be one of his invitees, but instead outlines evidence that each person, independently of the others, might be a werewolf. Given the existence of such creatures, Newcliffe has presented a situation in which anywhere from none to all of his special guests might be werewolves rather than one, no more and no less.
[At the beginning of the film, with narration] This film is a detective story--in which you are the detective The question is not "Who is the murderer?"--But "Who is the werewolf?" After all the clues have been shown--You will get a chance to give your answer. (Said but not written on screen, directly after above quote: Watch for the werewolf break).
English