From the publisher's website
Hideouts & Hoodlums is a modification of the Swords & Wizardry rules from Mythmere Games. What the Open Game License has allowed me to do is make a game as close to the original fantasy roleplaying game as possible BUT with swords and sorcery elements expunged and replaced with elements of the Golden Age of the superhero genre, circa 1939.
From the Men and Supermen introduction
INTRODUCTION: HIDEOUTS & HOODLUMS is a fantasy roleplaying game, but not the type of fantasy where sword-wielding barbarians kill hordes of orcs while robed wizards shoot fireballs at dragons. This is the fantasy world of the superhero genre. The genre created by writers like Siegel, Robinson, and Kirby is surprisingly similar to the genre of Burroughs, Tolkein, and Howard. Both are escapist fantasies of, largely, male wish fulfillment. Both are morally simple worlds of good guys and bad guys.
As I grew up, reading comic books and then taking to DUNGEONS & DRAGONS, I often wished there was a way to combine my two passions. Many game systems have come and gone in the 26 years since I started gaming that attempted to do just that, but none of them greatly resembled D&D. In time, I realized that too many superhero games were obsessed with endless customization, while part of the charm of D&D was its very limitations - its limited archetypes with their preset paths from obscure novices to powerful uber-heroes. And, while I grew up with the comic books of the ‘70s, I also came to realize that an Old School superhero game should seek to capture the feel of Old School superhero comic books as well. In both cases, I have gone as close to the original sources as copyright laws allow.