Superman The Mad Scientist (1941)
The Man of Steel fights a mad scientist who is destroying Metropolis with an energy cannon
Superman Electric Earthquake (1942)
Superman versus a fanatical extortionist with an earthquake machine
Superman The Mechanical Monsters (1941)
Superman battles a criminal mastermind and his robot army
Superman Showdown (1942)
A crook dressed as Superman commits a series of robberies The real Superman must work fast to counter the bad publicity