Pulp magazines and movies were big at the same time making the crossover a logical idea. The consumer in the 1930s and 40s had a choice. Spend a few nickels to see a musical or a b&w noir pic or buy a copy of Weird Tales, Ranch Romance, Flying Aces or any of the other three hundred titles. There was no television yet, though Radio was making itself felt, and how else could you spend your leisure hours? For the SF fan (say in 1935) that meant either Flash Gordon on the big screen (and in the papers), a copy of the Tremaine Astounding or the Buck Rogers Radio show.
SF Pulps
As the Science Fiction Pulps rose up from the rickety Amazing Stories of Hugo Gernsback, and films with glorious special effects became more and more common, it makes sense that film producers would want to promote their movies directly to fans of Science Fiction. Edgar Rice Burroughs, a savvy business man, got the connection in All-Story Weekly (June 30-July 14, 1917) with his “The Lad and the Lion” (May 14, 1917) crossover.
Here are a few other rare attempts to do that:
Dr Cyclops (1940) had an adaptation by Henry Kuttner in Thrilling Wonder Stories, June 1940.
1957’s 20 Million Miles to Earth had an Amazing Stories novel written by Henry Slesar. Movie tie-in novels would become common with paperbacks but here is an early attempt.
Radio
The Science Fiction magazines, no longer thought of as Pulps, used Radio at a time while television was just starting. Radio shows like Tales of Tomorrow, X-Minus 1, Dimension X, didn’t feature the stilted lowest common denominator radio antics of Tarzan, Buck Rogers and Flash Gordon. The 1950s shows selected the best of Galaxy and Astounding Science Fiction with authors like Ray Bradbury, Isaac Asimov, Fredric Brown, Robert A. Heinlein, Fredrick Pohl and others. The magazines received a plug at the beginning and end of the show.
Novelizations
Doctor Who, Star Wars and Star Trek books (adaptations and new material) have sold millions of copies despite the fact that many are hardly good reading. Novelization reading is almost a different activity to reading original fiction, a kind of halfway state between media and imitation, a true crossover. (It keeps Alan Dean Foster in groceries anyway.)
Comic Books
The comics were always way ahead of Pulps on this. This shouldn’t be surprising since by 1955 most pulps were dead and comics were entering their Silver Age. There were comics that did nothing but movie adaptations like Movie Comics and Motion Picture Comics. Others that like Dell’s Four Color, that featured comic, cartoons and television and film crossovers. Westerns dominated all titles.
Conclusion
Today the comics and the movies are owned by the same company, and it gets hard to tell if one is merely an ad for the other. Disney having control of such properties as Marvel Comics, The Muppets and Star Wars, as well as the TV network ABC, Touchstone Pictures, and its own Disney Plus channel, production is a multi-layered affair with entertainment, comics, video games, toys, etc. all promoting each other. A program like The Mandalorian can seem to be everywhere before, during and after airing. This makes The Lad and the Lion or Dr. Cyclops look like peanuts, but it was the beginning of crossover promotion.
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