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...