The Royal Flush Murders — Gerald Verner

Superintendent Budd is called in by the local police of Long Millford to investigate the strange murder of John Brockwell, impaled to the trunk of a tree with a pitchfork. Pinned to the lapel of the dead man's jacket is a playing card: the ten of diamonds. What is the meaning of this sign left on the body? Who hates the unpleasant Brockwell family so intensely, and why?