This twelve-episode serial from Mascot Pictures presents the story of the Whispering Shadow, a criminal who induces others to commit crimes as he controls them with television and radio rays. He leaves a wake of carnage as he searches for jewels belonging to the Czar. Detectives are under pressure to locate and apprehend the mastermind. Interesting note: the film was one of two of the highest paid projects of Bela Lugosi's career, and Karl Dane's last film.