"The British Secret Service, working to uncover a large-scale blackmail ring and catch its mastermind 'The Spider,' find themselves at the country residence Feltham Abbey, where a fancy-dress ball is in full swing. In the chaos of celebration, Sir Ralph Feltham is discovered dead and Tony, a bewildered yet curious guest, sets out to make sense of the night's activities as well as the motives of the other benevolent-appearing partygoers. This classic...