When they came to comics, Superman had been around for about a year, and the medium was still in its infancy. They took the action and made it explode, breaking out of the panels and sprinting across the page. They showed what comics could do, experimenting with layout and design, creating the first full-page panels and double page spreads.

Their first million-seller was a superhero (Captain America), and their next was military adventure that outsold Superman (DC's Boy Commandos). These two guys from...