The game, of course, is Cluedo, and yesterday the fourth best-selling game in the UK celebrated its 50th anniversary. Hasbro, the manufacturer, had gathered together 50 Miss Scarletts, the world Cluedo champion and George Gowler, a sprightly 87-year-old who rejoiced in having been Agatha Christie's butler.
Unfortunately, things did not go entirely to plan. The firm had invited 50 "curvaceous young ladies who own a red dress" to join the celebrations. But as they paraded around a park in south London for the photographers, someone called the police, claiming they had seen a crowd of people brandishing weapons. Six police cars, sirens blaring, descended. In the ensuing confusion and pouring rain, it was discovered that some of the Miss Scarletts had been supplied by modelling agencies and were being paid.
Esther Samuels, 17, who had persuaded her father to part with pounds 60 for a beautiful red dress, was distraught. Her mother, Janet, was furious: "That dress is ruined," she said. "It was freezing out there. I hope they will pay the cleaning bill."
Back inside, Josef Kollar, the world Cluedo champion, was enjoying himself before taking part in a game to mark the anniversary.
"Colonel Mustard fancies Mrs Peacock," he said. "And Miss Scarlett is actually Mrs Peacock's daughter - but they like to keep it quiet." Somewhat surprisingly, he added: "I do like Cluedo but you can't beat a good game of Monopoly."
More than three million copies of Cluedo are sold every year in 23 countries. The game was invented in 1943 by Anthony Pratt, a solicitor's clerk, who enjoyed murder mysteries. He showed it to Waddingtons in 1945. The firm spent four years perfecting the game before launching it. Success, however, proved elusive, and in the early 1950s Waddingtons wrote to Mr Pratt, saying that sales were not going well. He signed over the royalties for a mere pounds 5,000 and died a poor man in Bromsgrove, Worcestershire.
Since then, the game, now owned by Hasbro, has gone from strength to strength. With six characters, six weapons and nine rooms there have been a potential 324 different murder combinations. Now poison has been added to the suspects' array of aids.
"It's usually Colonel Mustard," said Mr Kollar, which only goes to prove that even world champions can occasionally get it wrong. This time it was Miss Scarlett, in the dining room, with the candlestick.