debut in the starring title role) - it was the classic tale of a scientist with a formula for invisibility accompanied by spectacular special effects and photographic tricks.

Mad Scientists in Early Horror/Sci-Fi Films:

In the 1930s and early 40s, American sound films with hybrid science fiction/horror themes included an oddball collection of mad scientist films, with memorable characters who created mutated or shrunken creatures:

The Vampire Bat (1932) - a low-budget Majestic Pictures film in which Lionel Atwill starred as mad doctor Otto Von Niemann, responsible for creating bloodsucking nocturnal bats in a small German town; with a cast including dark-haired, 'scream-queen' Fay Wray, Melvyn Douglas, and Dwight Frye (the crazy Renfield character in Dracula)
Doctor X (1932), a First National (later Warner Bros.) film, in pioneering two-strip Technicolor by directorMichael Curtiz, about another mysterious mad scientist named Doctor X-avier (Lionel Atwill) and his daughter (Fay Wray)
The Mystery of the Wax Museum (1933), another First National film in two-strip Technicolor, about an insane, wax-dummy maker-sculptor, again pairing Atwill and Wray, and featuring Glenda Farrell as a fast-talking, wisecracking reporter; famous for the shocking 'face-mask crumbling' scene; [re-made in 1953 as House of Wax with Vincent Price]
The Black Cat (1934) - the first and best of all the Karloff-Lugosi pairings at Universal, featuring Boris Karloff (as a crazed devil worshipper) and Bela Lugosi (as a vengeful architect)
The Invisible Ray (1936) - although he usually played a grotesque monster, Karloff starred as experimental physicist Dr. Janos Rukh in this film; after traveling to Africa with his colleague Dr. Benet (Bela