The Human Monster (1939)

Starring Bela Lugosi, Hugh Williams, Greta Gynt, Edmon Ryan, Wilfred Walter
Directed by Walter Summers
(actor & director credits courtesy IMDB.com)

An insurance broker uses trickery and forgery to cash in on men's life insurance policies after he murders them, but a Scotland Yard investigator and an American detective are on his trail. 

Edgar Wallace's story The Dark Eyes Of London is adapted into a vehicle for star Bela Lugosi in this British film, and has a pretty good screenplay, with roles for Gynt as the daughter of one of the murder victims ready to track down his killer,  and Ryan as the American detective who provides comic relief.  Lugosi is in good form as the criminal mastermind, employing icy stares and mirthful expressions beneath a friendly warm facade.  Using a home for the blind as a front for his nefarious activities, he also employs a grotesque henchman (played by Walter in a hideous makeup) whose stalking of the leading lady makes for some of the film's most suspenseful scenes.  My only real disappointment with the film has been the difficulty of finding a copy with good audio.  Much of Williams' dialogue is either badly recorded or drowned out on the soundtrack in the prints I've viewed, forcing me to watch the film with subtitles.

Sexton Blake And The Hooded Terror (1938)

Starring George Curzon, Tod Slaughter, Greta Gynt, Tony Sympson, Charles Oliver
Directed by George King
(actor & director credits courtesy IMDB.com)

The head of a secret society of criminals plans a conference with his lackeys in London, but before long reputed detective Sexton Blake is on the villain's trail.

This film offers a bit of a departure from the usual vehicles for British thespian Tod Slaughter, not playing a psychotic killer here, but a master criminal, and also deferring top billing to Curzon's Sexton Blake.  The Slaughter/Curzon interplay comes off very similar to the Professor Moriarty/Sherlock Holmes dynamic in the stories of Sir Arthur Conan Doyle.  Nevertheless, Slaughter is again fine in his role, plotting his evil schemes from behind a wispy beard, and lusting after his henchman's attractive girlfriend, in reality a covert agent for the French government.  As with the other Slaughter/George King collaborations, the pacing is exciting and the unveiling of the plot well-done, a fine complement to Slaughter's engaging performance.