Dr. Janos Rukh (Boris Karloff, The Ape) is a brilliant astronomer who invites Sir Francis Stevens (Walter Kingsford) to the unveiling of his latest invention, a device which allows him to see into the Earth’s past by riding the light sent from stars backwards in time and reversing his viewpoint so that he can see the Earth. Accompanying Stevens are his wife, Lady Arabella (Belulah Bondi, Remember the Night), the famed explorer Ronald Drake (Frank Lawton, The Devil Doll) and Dr. Felix Benet (Bela Lugosi, The Corpse Vanishes), a medical researcher who seeks to protect Stevens from a hoax, but whose objections fade once he sees Rukh’s achievement. Rukh’s device detects the impact in Africa of a meteor composed of a new and extremely powerful element, Radium X. Rukh and his guests begin a joint expedition to find the impact site and prove the power of Rukh’s device.
Everything is not perfect, however, as Rukh’s blind mother (Violet Kemble Cooper, The Invisible Man) warns Rukh that he does not understand the outside world. Rukh certainly understands people too little to see his wife Diane’s (Frances Drake, Mad Love) growing attraction to Ronald, a situation exacerbated by Rukh’s decision to take native bearers and look for the meteorite on his own. When Rukh finds and enters the crater, the sample he brings out is able to power a death ray-but so contaminates him that his very touch is deadly. Dr. Benet is able to devise a treatment, but he fears that the Radium X will cause Rukh’s mind to deteriorate-and Benet’s serum can only hold the contamination in check, not remove it. When Rukh’s partners return to Europe and begin to exploit the sample Rukh gave Benet to achieve medical advances and Diane’s infidelity is revealed, Rukh fakes his own death and begins stalking the six members of the expedition, using his deadly touch to murder them. Can Benet and the police stop Rukh before he kills again?
The Invisible Ray is an enjoyable mad scientist film-perhaps not up to the same standard as the great Lugosi/Karloff collaboration, The Black Cat, but fun in its own way. Karloff’s Rukh is an excellent example of the mad scientist as a good man gone bad, while Lugosi’s Bennet is one of his rare heroic roles. Lugosi plays the role for all it’s worth, giving a solid performance. Sadly the rest of the cast is either generically serviceable or actively irritating, especially Frank Lawton and Frances Drake. While Drake is quite attractive, the pair lacks chemistry and Lawton’s is an odd choice to play a famed explorer.
The film also jumps about a bit too much, going from Rukh’s Gothic lab to darkest “Africa” (i.e. a studio back lot peopled with racist caricatures and stodgy white men in Pith helmets) and then to France, shifting from a mad scientist film to a jungle picture to Rukh as a monster who glows in the dark and whose touch kills. The middle African section deserves cutting the most, though one wonders if the Vibranium meteorite in Marvel Comics Wakkanda doesn’t draw inspiration from this film. Director Lambert Hillyer (Dracula’s Daughter) adds little life or flair, and at times delivers a film that is only a tiny step up from the serials of the time, particularly in the African sequences. The Invisible Ray is a solid, if unexceptional, mad scientist film, mainly worth seeing for the leads performances and the arresting final act.