Sue Storm / Invisible Woman: While she was still quite young, Sue became smitten with her aunt's handsome and brilliant tenant, science prodigy Reed Richards; a university student at that point. Sue and her brother Johnny insisted on coming on the maiden voyage of Reed Richards' experimental starship. But inadequate shielding allowed mysterious cosmic rays to penetrate the ship's hull and bombard the crew, forcing them to crash-land back on Earth. Upon landing they discovered that they had gained superpowers, and Sue became the "Invisible Girl."
The Mole Man: The Mole Man launched his first known attack on the surface world, dispatching his Mutates to destroy power plants in prepartion for an all-out invasion; however, his campaign had only just begun when he attracted the attention of the newly-formed Fantastic Four. Entering ther realm of Subterranea via its Monster Island entrance, the FF defeated the Mole Man and his army of monsters in the first of many confrontations.