Origin

Mighty Mouse is a character of amazing mystery. This super-powered mouse was originally a unique house fly. He originally had a blue costume with a red cape, like Superman, but over time this changed to a yellow costume with a red cape. Mitzi, his girlfriend, is in almost every comic he is in, as are his arch-enemies, the Claw Gang, who are really just cats. Lured by cheese, he gets into a tight squeeze once. Later, he is almost killed by his new arch-nemesis Oil Can Harry, a brilliant cat inventor gone bad. Using his knowledge of electronics, Harry creates soldiers and conquers Mouseville until Mighty Mouse and the soldiers chase him to the North Pole. Mighty Mouse demonstrated time travel and fought three dinosaurs. Cavemen begin to worship him until he returns to the present. When he gets back, he notices that Mitzi Mouse is nowhere to be found. But he smells it: The Claw Gang! He follows the scent to an abandoned warehouse in downtown Mouseville. There he sees the dead body of Mitzi...

Mighty Mouse is so depressed that he joins the evil doers that seemingly killed his beloved, until he realizes his idiocy and puts them in jail.