It's 1958 and Lord James and his wife Beth are hosting the annual spring fair. Then wealthy recluse, Delphine Brooks-Hunter is murdered. James is summoned to the reading of her will and is tasked with solving an intriguing riddle. Meanwhile, Beth tackles her own mystery after discovering a homeless man suffering from amnesia. As they delve deeper, a number of questions emerge. What links Delphine to the fairground folk? Who would harm such a refined lady? Are rumours of World War espionage true? As they unravel the truth, they uncover far more than they ever bargained for.