Superman and Batman kicked off the Golden Age of comic books and popularized the concept of the superhero with their debuts in the late 1930s. But did you know that pre-comic book versions of these characters were both bad guys? So much of what we know and love about the heroes today originated outside the comic realm. 

Kryptonite, Jimmy Olsen, the Bat Cave and so much more started in other media before eventually being pulled into comics canon. Taking these characters off of the page to radio, TV, and movies put any missing pieces on full display and required creative thinking to solve. Sometimes it wasn’t an official Batman or Superman property that served as an inspiration for the comics, but another creator’s work entirely. We’ll take a look at lore elements from these legendary characters that most of us assumed were always baked in.