When Harry Marsland was caught in a sudden down pour he sought shelter at Cliff Farm. Met at the door by a young woman clearly expecting someone else he is only too glad to get inside to wait out the storm. When they hear a noise upstairs in the deserted house they investigate only to discover the body of the farms owner, Frank Lumsden, dead of a gunshot wound. Who then, killed Lumsden, and why? Who was the woman expecting and did she have any roll in the murder? These are the questions that private detective Crewe must answer in The Mystery of the Downs.