Mr. Mind made his debut in 1943 in what's commonly regarded as one of the most important and, on some levels, the best story of the entire Golden Age of Comics: "The Monster Society of Evil."

That big high concept? Instead of having a single villain show up to battle the hero and then be defeated at the end of the story, creators Otto Binder and C.C. Beck decided to bring back all of the villains and unite them into a single monstrous, evil society called, well, the Monster Society of Evil. If that seems like a pretty simple idea, that's because it is, and it's one that superhero comics would go back to every time they needed to raise the stakes. Keep in mind, however, that this was only five years after Superman made his first appearance, when the superhero genre was in its infancy. Most super-villains at the time were meant for single stories, and bringing them back as a united force was pretty revolutionary.

The way that the story was told was a whole new idea, too. In a time when most comics contained multiple self-contained stories that crammed a beginning, middle, and end into as few as 8 pages — something that would be a pretty standard practice until the dawn of the Marvel Universe nearly 20 years later — "The Monster Society of Evil" took its cue from movie serials. Starting in Captain Marvel Adventures #22, the story sprawled out over the next 25 issues before finally wrapping up after two years of comics. That's a long story by today's standards, and in the Golden Age, it was downright epic in every sense of the word. And Mr. Mind was right at the center of it.