An Italian-French-Spanish version of the much-filmed Agatha Christie story, this film is strangely set in Iran, not Great Britain. Ten guests are invited to a remote desert inn and informed that the mysterious host has described in a nursery rhyme how they will all die during the gathering. One by one, the characters, played by such Continental stars such as Elke Sommer and singer Charles Aznavour as well as Britons Oliver Reed and Richard Attenborough, dwindle in number, each in accordance with a verse of the nursery rhyme, until only a few remain. The final characters then plot to ensnare the criminal mastermind behind the weekend of mayhem.