The Twenty-One Clues
The Twenty-One Clues is a 1941 detective novel by the British author Alfred Walter Stewart, published under his pseudonym J.J. Connington. It is the fourteenth in a series of seventeen novels featuring the Golden Age Detective Sir Clinton Driffield, the Chief Constable of a rural English county. It was published by Hodder and Stoughton in London and Little, Brown and Company in the United States.