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.

Miss Scarlet (Lesley Ann Warren) is a character from the board game, Clue. In the film adaptation, she is a socialite who runs an illegal escort service, for which she is being blackmailed by Mr. Boddy. In one of the ends, she killed the cop in the library with a lead pipe.

Uncle Fester, also known as Fester Addams, is a member of the fictional Addams Family. He was played by Jackie Coogan in the original television series, by Christopher Lloyd in the two feature films. He’s also the player character in the infamous video game Fester’s Quest, reviewed by The Angry Video Game Nerd

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.

Yvette (Colleen Camp) is Mr. Boddy’s maid in the film, Clue. She is also Mr. Boddy’s accomplice, a former escort for Miss Scarlet, where she had Colonel Mustard as a client, and one of Miss Scarlet, Mrs. Peacock, or Mrs. White, depending on the ending.

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.