Superman; Rokk (intro, villain, next appearance in WORLD'S FINEST COMICS #150); Sorban (intro, villain, next appearance in WORLD'S FINEST COMICS #150); Lana Lang (guest star); Professor Potter (1st appearance in SUPERMAN); Jimmy Olsen; Lois Lane; Perry White
Superman; Mr. Mxyzptlk (villain); Douglas Parker [ex-Smallville Chief of Police, Chief Parker] (guest appearance); Lois Lane; Perry White
Mr. Mxyzptlk from the 5th dimension stops by briefly to curse Superman: everything he says becomes a reality -- literally! Soon, Superman is afraid to even open his mouth, but the curse is lifted when Superman says his own name backwards.
Superman; Dr. Luring (intro); a tribe of cavemen (intro); Lois Lane; Jimmy Olsen
Superman ends up on a planet under a red sun and loses his superpowers. A caveman strikes him down and steals the Superman suit -- Superman, who was once the strongest man alive, is now the weakest! Eventually, Superman is rescued by his friends Jimmy Olsen and Lois Lane, who have arrived from Earth in a spaceship.