Trivia: Professor Plum reveals that he works for UNO, the United Nations Organization, in a branch called WHO, the World Health Organization. As such, he works for UNOWHO (You Know Who).
Trivia: Not a mistake, just a neat little fact. When the film was being shown at cinemas, only one ending was shown. Different venues had different endings.
Trivia: Professor Plum hypothesizes to the group that the brandy was poisoned. In the original Cluedo board game, poison was included among the possible weapons, and later re-introduced in 1990's game Clue Master Detective.
Trivia: Miss White's "flames on the side of my face" line was ad-libbed by Madeline Kahn.
Chosen answer: Tim Curry (as Wadsworth) states he knew about the secret passages because the house belongs to a friend of his. Tim Curry (as Mr. Boddy) says at the end of the movie that they "Could stack the bodies in the cellar and could all leave one by one." Which infers that Mr. Boddy has no intention of returning to the house. Either way, there is no definite way to tell who the house belongs to considering all the lying going on.
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