The endless reaches of outer space are nothing compared to the vast depths of popular culture, which run so deep that they accommodate two completely different comic-book superheroes with the name “Captain Marvel.” Each is owned by a different publisher; each comes complete with their own complicated backstory and sprawling cast of characters. In each case, there have been multiple individuals who bear that name “Captain Marvel” at different times. And somehow, by cosmic coincidence and the vagaries of the intellectual property market, both of the two Captain Marvels will soon star in their own big-budget Hollywood movie released within a few weeks of each other: first Marvel’s Captain Marvel, and then DC’s Shazam! In comic-book terms, it would be described as an epic battle: Captain Marvel vs. Captain Marvel.

The first of the two new Captain Marvel movies, due on March 8, is based on the Marvel Comics character, who has been around for 50 years. But this Captain Marvel is a newcomer compared to the original Captain Marvel, created in 1939 and returning to the big screen April 5. The first Captain Marvel was one of many bullet-proof, airborne strongmen created in the wake of Superman, the literary creation who simultaneously mass-popularized the closely intertwined concepts of the costumed superhero and the four-color comic book.

When the original Captain Marvel, created by writer Bill Parker and artist C. C. Beck, premiered in February 1940, their Kryptonian inspiration was undeniable: the bright, primary-colored tights (red rather than blue); the insignia (a lightning bolt rather than a big red “S”)); the cape; the boots; the secret identity; the chiseled chin and rugged good looks. On the cover of Superman’s first appearance, in Action Comics #1 (published by the company that later became DC), the Man of Steel is shown lifting a car, and is presumably about to throw it; on the cover of his debut in Whiz Comics #2 (published by Fawcett Comics), Captain Marvel is hurling a car and the bad guys in it against a brick wall.

Yet the first Captain Marvel was still very much his own man; his origin and powers were rooted in magic and fantasy rather than Superman’s fictitious science, and his alter ego was Billy Batson, a tween boy who transformed himself into an adult hero by uttering the magic word: “Shazam.” That element especially struck a chord with the comic-book industry’s core audience of young male readers; the idea of becoming a grown-up flying hero by saying a magic word resonated more strongly than being born on another planet and disguising oneself as a mild-mannered reporter. Captain Marvel’s adventures were also much more whimsical than Superman’s—and gorgeously illustrated (and frequently written) by Beck, who often seemed to be spoofing the superhero genre even as he was helping to invent it.

This Captain Marvel’s central villain and nemesis was a grumpy, bald-headed evil scientist named Doctor Sivana, who was clearly an overt parody of Lex Luthor-like evil scientists. He referred to the Captain as the Big Red Cheese. They existed in a universe partially populated by anthropomorphic “funny animal” characters, like Tawky Tawny, a talking (and conspicuously clothed) tiger, and the villainous Mr. Mind, a bespectacled worm who spoke by means of a teensy amplifier around his neck.

In 1941, Captain Marvel became the first superhero to star in a live-action adaptation: Republic Pictures’ classic movie serial, The Adventures of Captain Marvel. The Big Red Cheese was also the center of a comic-book franchise, although he didn’t have a love interest à la Lois Lane or a kid sidekick like Robin, either. But he did have a female counterpart, Mary Marvel (Billy Batson’s sister), as well as an entourage of three Lieutenant Marvels, a W. C. Fields-like Uncle Marvel, and even Hoppy the Marvel Bunny (don’t ask). There was also Captain Marvel Jr., a disabled teenager who transformed into a Superboy-like figure—a favorite of a young Elvis Presley.