Ed Godziszewski wrote:One of the biggest concepts that was scripted but ultimately turned down was Frankenstein vs Godzilla. Just like King Kong vs Godzilla, it made sense in that it was a pairing of two famous icons. But in my opinion, the ultimate downfall of the idea was that it would make the fatal flaw of putting Godzilla on screen with a non-costumed human actor. No matter how well filmed, the image of Godzilla as a giant creature would irreparably be damaged. And while you can suspend disbelief and imagine a creature like Kong might be able to withstand Godzilla’s ray to some extent, that’s a much tougher sell with a human figure. I think it was a wise move to tweak this story into what eventually became Frankenstein Conquers the World. The Frankenstein monster was wisely downsized by half of what he would have been if he had faced Godzilla, and they created Baragon as a more evenly-matched opponent. Since Frankenstein was not a costumed actor, the change in scale actually benefitted the film since it was an easier sell the image of a human monster as believable in 1/12 scale.
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