Okay, note to the people that put together these horror acting legends DVD-collections: I truly am grateful and I hugely support the initiative, but  have you even watched the films before selecting them as part of the collection? When I purchased the Boris Karloff collection there were several films in which the star only played a supportive and unessential role ("Tower of London", "The Strange Door"). "The Invisible Ray", however, is part of the Bela Lugosi collection and here it's actually Boris Karloff who overshadows Bela! This actually would have been a great title for the Boris Karloff collection instead! Bela Lugosi's character is quite possibly the most good-natured and earnest one he ever portrayed in his entire career and good old Karloff actually plays the mad and dangerously obsessed scientist here. "The Invisible Ray" features three main chapters. The first one, set in Dr. Janos Rukh's Carpathian castle is pretty boring and demands quite a lot of the viewer's patience, but of course the character drawings and the subject matter discussed here are fundamental for the rest of the film. Dr. Rukh (Karloff) demonstrates to a couple of eminent colleagues (among them Bela Lugosi as Dr. Benet) how he managed to capture extraterrestrial rays inside a self-manufactured device. The scientists are sincerely impressed with his work and invite Rukh and his lovely wife Diane along for an expedition in the heart of Africa. There Dr. Rukh isolates himself from the group, discovers the essential element "Radium X" to complete his medical ray and goes completely bonkers after being overexposed to the meteorite himself. The third and final act is obviously the best and most horrific one, as it revolves on a good old fashioned killing spree with ingenious gimmicks (melting statues) and a surprising climax. Karloff glows in the dark and, convinced the others are out to steal his discovery and even his life, he intends to eliminate them using his deadly touch. The narrative structure of "The Invisible Ray" sounds rather complicated, but the film is easy to follow and entertaining. The story is rather far-fetched but nevertheless compelling and director Lambert Hillyer provides several moments of sheer suspense. Boris Karloff is truly fantastic and so is Lugosi, even though he deserved to have a little more screen time. Their scenes together are the highlights of the film, along with the funky images of the glowing Boris.