Mysterious Dr. Satan - 1940 Cinema Serial Ep. 06 Double Cross

Mysterious Doctor Satan (also known as Doctor Satan's Robot) is a 1940 American film serial directed by William Witney and John English. Produced by Republic Pictures, the serial stars Edward Ciannelli, Robert Wilcox, William Newell, C. Montague Shaw, Ella Neal, and Dorothy Herbert. The title of the serial is derived from that of its chief villain. Doctor Satan's main opponent is the masked mystery man, "The Copperhead", whose secret identity is Bob Wayne, a man searching for justice and revenge on Satan for the death of his guardian Governor Bronson. The serial charts the conflict between the two as Bob Wayne pursues Doctor Satan, while the latter completes his plans for world domination.