11. Dr. Satan's Robot - Mysterious Doctor Satan (1940)
In this not-quite-superhero serial from the 1940's, a mad scientist named Dr. Satan attempts to steal technological secrets that will allow him to build an army of robots to conquer America. Our hero, the Copperhead, is the only thing that can stop the tin can robot and his dryer hose arms.
Estimated chance you've seen this one: 6%