'Cluedo' is a video game based on the famous Parker Brothers board game, which is called 'Cluedo' in Britain but 'Clue' in America. Although retaining the British name for this video version, and using a British cast, the producers seem to be making entente with American video gamers. One of the characters in this game is named Mr Green, as in the American board game. In the British version of this game -- which actually pre-dates Parker Brothers' American version -- the same character is named Reverend Green.
I should explain the different names. In the early 20th century, there was a very popular board game in Britain called 'Ludo', from the Latin for 'I play'. Ludo is probably the best example of an absolutely generic board game: it consists of counters moving along squares on a board, with no specialised theme as there is in Monopoly or Risk. When the murder-themed board game was invented, it was named 'Cluedo' in Britain to rhyme with 'Ludo'. As Ludo was never popular Stateside, the Yank version of Cluedo was cried 'Clue'.
This video version has the same premise as the board game. Mr Boddy has been murdered. Each of his guests (as well as the butler) is a possible suspect. All of them join forces to solve the murder, apparently unconcerned that the murderer will queer the investigation. The players must determine who committed the murder, with what weapon, in which room of the house. (Shouldn't the location of the body indicate the murder scene?) Because this is a video game, designed for repeated replays, there is no single 'correct' solution. The two most eccentric characters are played by the two best-known actors in this cast, Joan Sims and John Standing. The graphics and audio are not especially impressive. You'll have a better time playing the board game. Hell, you'll have a better time playing Ludo.