ObscureHollywood.net’s review published on Letterboxd :
Johnny Arthur, newly minted correspondence school private detective, is trapped in a creepy mental sanitarium with his sweetheart and a “sheik-like” rival for her affections. The sanitarium is overseen by the inmates, led by Lon Chaney, a demented surgeon. Chaney’s assistants have been trying to obtain a man and woman on whom Chaney can perform his experiment in mental transference. The sweetheart and the rival nearly become his victims, but Johnny saves them by capturing Chaney and his deranged crew.
Lightweight comedian Johnny Arthur has the main role as the seemingly hapless, but actually quite resourceful, detective. Utilizing a minimum of make-up (for him), a variety of facial expressions, and some menacing pantomime, Lon Chaney produces a frightening characterization.
The film is based on a 1922 stage play of the same name, written by the prolific Crane Wilbur. Wilbur’s acting career began in 1911 and included roles on stage and screen, including the hero role in The Perils of Pauline (1914). He also directed stage plays and numerous silent and talkie shorts. However, his main career credits are as an author, for stage and screen. Among his 80 screen credits are He Walked by Night (1948) and House of Wax (1953).