The Quartermain Mysteries

At twenty-five years old Anna, Lady Quartermain, becomes a wealthy widow. In an attempt to restart her life she sets up the Wellington Bureau, an investigation agency. A series of cases follow in which Anna unravels a number of mysteries, including those surrounding the fabulous diamond, the Quartermain Stone. The Wellington Bureau, The Eleventh Commandment, The Five Gold Rings Mystery, The Fifth Plinth, The Quartermain Stone Mystery.