 Birtwhistle has been ill for the past two years, and in that time Sybil has taken over the actual writing of his novels, an arrangement that has led to increased sales due to Sybil's greater gifts for character and dialogue.However, she has come to suspect that someone in the house might be keeping Humphrey ill through drugging, so as to keep Sybil writing and bringing more money to the farm.Then when Humphrey dies, foul play is suspected, and Daisy begins to investigate as her husband, Chief Inspector Alec Fletcher, is called down from Scotland Yard to take the case.