The ruthless Wasp wants professor Houston's (Forbes Murray) powerful new radium energy machine so he can accomplish his dastardly goals of blowing up a radio station, a power plant and a dam. Can Mandrake (Warren Hull) halt the villain in his evil tracks? The suave, quick-witted magician will have to if he hopes to save the planet and win the heart of Houston's comely daughter, Betty (Doris Weston), in this rollicking 1939 serial.