The Hampstead Mystery is written by John R. Watson & Arthur J. Rees. The story starts with inspector Seldon and Flack approaching the Rivers brook mansion. With the large, antique brass knocker, Inspector Seldon forcefully banged on the front door. He waited patiently for a response, but other than the harsh tone of an electric bell, nothing else was heard. Inspector Seldon immediately circled the house's side, checking the windows along the way. On the exterior woodwork, he noticed that one of the catches had been damaged. Inspector Seldon strolled along the corridor, shining his torch into each room as he went. Inspector Seldon carefully examined the hangings and the figure. It was misaligned and on the verge of falling off its pedestal. A door on the right, in the passage just beyond the landing, was thrown wide open. Inspector Seldon found Flack kneeling beside the body of a man who had been dead for hours. He discovered the wound where the blood had come from over his heart. He added, lightly caressing the wound, "It doesn't take a big wound to kill a guy.