10. Fighting Nazi Aliens With Orson Welles - Superman #62 (1950)
If Superman teaming up with Citizen Kane actor, Orson Welles, to battle aliens sounds like a ludicrous idea, that's because it is.
The comic begins with Welles working on his latest film before noticing an alien spaceship nearby. Curious, he enters the vessel only to have the door behind him seal shut. The ship automatically travels to Mars where Welles stumbles upon an alien called Martler.
Martler explains how he used a radio to study Welles' homeworld. When he learned about Adolf Hitler, Martler was won over by the dictator's rallying speeches and thus, formed a group of Nazi Martians called The Solazis. Just to be as unsubtle as possible, Martler wears a Gestapo uniform and sports a Hitler moustache!
Welles uses the aliens' radio to send a SOS message to Earth. Since Welles faked an alien invasion on the radio several years prior, the people of the world ignore his plea. Superman uses his super-hearing to validate that Welles is actually on the planet, Mars. After he flies over to the red planet, Supes allies with the Oscar-winning actor to thwart the Solazis.