Boris Karloff discovers a powerful element, Radium X, which causes him to become lethal to the touch. Bela Lugosi is a colleague who develops a serum to keep these effects dampened. He also finds a way to use Radium X as a powerful healing device. Karloff, affected by both Radium X and side effects of Lugosi's serum, is filled with murderous jealousy and turns against everyone who was involved in his discovery.
The Invisible Ray (1936) demonstrates some wildly improbable "science" in the method used by Karloff's character to discover the meteor that brought Radium X to earth. In spite of that it is a pretty decent film filled with some really nice production design, a heroic Lugosi, and a less than sympathetic Karloff as the socially aloof scientist with the killing touch.