In Clue, the Singing Telegram Girl (Jane Wiedlin) is a character who visits Mr. Boddy’s party to deliver a message, before being killed by one of the guests. She is later revealed to be a former patient and lover of Professor Plum’s.

In Clue, Mrs. White (Madeline Kahn) is a “black widow” who had her husbands disappear or die mysteriously. She is a guest of Mr. Boddy’s, and is also being blackmailed by him. The maid had an affair with one of her husbands, so in one of the endings, she killed the maid in the billiard room with a rope.

In the film, Clue, Mrs. Peacock (Eileen Brennan) is the high society wife of a Senator. She is a guest of Mr. Boddy’s party, and is being blackmailed for accepting bribes to deliver her husband’s vote. To stay true to the board game, Mrs. Peacock killed the cook in the kitchen with the knife.

In Clue, Colonel Mustard (Martin Mull) is a guest of Mr. Boddy’s who’s being blackmailed for war profiteering. It’s revealed that he made his money from selling stolen radios on the black market, as well as having an affair with one of Miss Scarlet’s escorts. In one of the endings, he killed a stranded motorist in the lounge with a wrench.

In Clue, Mr. Green (Michael McKean) is a State Department employee and guest of Mr. Boddy. He is blackmailed for being gay, a secret which would cost him his job. In one of the endings, he is suspected of killing the singing telegram girl in the hall with the revolver. He ultimately reveals himself as an undercover FBI agent, who actually killed Mr. Boddy in the hall with the revolver.

Dr. Emmett Lathrop “Doc” Brown, Ph.D., played by Christopher Lloyd, is best friends with Marty McFly in the Back to the Future series. Brilliant but absentminded, he invents a time machine using a DeLorean, a flux capacitor, and plutonium stolen from Libyan terrorists. Great Scott!