The Honorable Daisy Dalrymple-Fletcher is in the countryside, visiting friends who, all unmarried, have recently bought a house together. Daisy and her husband Detective Chief Inspector Alec Fletcher, of Scotland Yard are invited for Sunday lunch at the house, where one of the women mentions a wine cellar which remains resolutely locked. Alec picks the lock but when he eventually opens the door, what greets them is the stench of a dead body. Now Daisy's three friends are the suspects in a murder and her husband is a witness... Daisy is determined to use all resources and skills to solve the mystery behind this perplexing locked-room crime.