"The Invisible Ray is a creepy, suspenseful, and thought-provoking science fiction film by Lambert Hillyer—relevant to Universal Monster buffs for directing Dracula's Daughter. Especially fascinating is the underlying message explored in this feature, which indicates that scientific discovery in the wrong hands can lead to devastating consequences—a prescient topic for a 1930s motion picture to examine... Also worth commending is the gravitas of Lugosi, who, though remembered for playing creeps, kooks, and creatures of the night, offers an uncharacteristically restrained and delicate performance in this film." - Jon Davidson, Midnite Reviews