The unrealized vision of Frankenstein vs. Godzilla
Who will reign supreme? And what will be left of Earth?!
Monster movie mashups are one of the most fun subgenres ever. House of Frankenstein and House of Dracula were made with the idea that there was big money in movie monsters interacting. What if Dracula met the Wolfman? What if the Wolfman met Frankenstein? What if all three duked it out in a blood-curdling battle royale? Then, when Universal released Abbot and Costello Meet Frankenstein, the formula proved even more profitable.
So, why wouldn't Frankenstein's monster take a trip to Japan? That was the question Toho Studios asked in 1963. The Tokyo-based studio was famous with American audiences for its Godzilla franchise of kaiju (or giant monster) movies. In '63, Godzilla was fresh from a bout with another American export, King Kong. The crossover release was the third film in both the Godzilla and King Kong series. More importantly, at the time, it was the second most profitable movie in Japanese history. It was time for Godzilla to square off with another monster movie titan.
According to Ed Godziszewski's The Illustrated Encyclopedia of Godzilla, the idea was initially to see Frankenstein battle a different monster named The Human Vapor. That movie would've seen Mizuno the Vapor Man return (after 1960's The Human Vapor), while a scientist named Dr. Gildor exhumes a man-made monster in Baron Von Frankeinstein's cemetery. Dr. Gildor brings the creature back to Hong Kong, where the monster comes back to life.
Unfortunately, that's where the story of Frankenstein vs The Human Vapor ends, because the screenplay was never finished. But Toho was still interested in using Frankenstein's monster in a big battle. So, the studio approached Karou Mabuchi, who determined that Godzilla was the only monster worthy of such an epic matchup. Mabuchi continued work on the unfinished screenplay, now retitled Frankenstein vs Godzilla.
In this new version of the story, Frankenstein is considered the bigger threat to mankind, and so the people of Japan use Godzilla in hopes of defeating the re-animated creature. Frankenstein's monster continues to grow, both in size and craftiness, terrorizing the countryside and jeopardizing life for everyone. It's only a matter of time before he starts eating people to satisfy his insatiable hunger. That's when Godzilla is spotted, frozen in the Bering Sea, so the Self Defense Forces of the Japanese army thaw the monster to lead him back to Japan for a hopeful victory.
In the explosive finale, the giant Frankenstein's monster is swallowed up by a volcanic fissure while Godzilla is washed away in a river current.
Although Frankenstein vs Godzilla ultimately went unmade, many of the story details were recycled for the later Frankenstein vs Baragon (also known as Frankenstein Conquers the World).