Ever since the end of the Great War, North Yorkshire brewers have selected a charismatic female employee to be a local queen and the face of their industry. This year's queen, clerk Ruth Parnaby, invites Kate Shackleton and her niece Harriet to accompany her to a garden party. But after a pub delivery man is found dead in the fermentation room, the list of suspects includes Ruth's father. Following The Body on the Train, this 12th mystery is murky, at best, and it's going to take Kate at her keenest to decipher the truth.