Great Diamond Mystery on AllMovie

This murder mystery certainly wasn't a typical Shirley Mason vehicle -- she was better known for her sunny, girlish portrayals. Here she is Ruth Wilson, a novelist whose latest book is a mystery based on the assumption that a murderer always returns to the scene of the crime. Her not-terribly original theory is tested when her sweetheart, Perry (William Collier, Jr.), is convicted of murdering his boss, Graves (John Cossar). Graves was a diamond merchant who accused Perry of stealing one of the precious stones. Ruth rents Graves' house in the hopes that the killer will show up. Several people come around, including Mallison (Philo McCullough), Graves' partner, who has always loved Ruth. Graves' old butler also shows up, asking for his job back. While courting Ruth, Mallison spends a lot of time digging around Graves' home for diamonds. He finally finds some in a clock. The butler comes rushing in and a shot is heard. The butler is the one who is hit, and he confesses he was the one who shot Graves -- that's right, the butler did it (at least it wasn't McCullough, who was famous for his villain roles). Perry is saved from the electric chair and he is happily united with Ruth.