The film's plot is unknown.
U.S.-Japan Collaboration: Godzilla is one of the ideas proposed during the late 1970's and early 1980's when no new Godzilla films were produced. The idea was promoted by UPA Productions' chief Henry G. Saperstein, who has been famous for his involvement in the creation of Frankenstein vs. Baragon, Invasion of Astro-Monster, and War of the Gargantuas. Speculation has arisen that the film was meant to be Godzilla vs. Gargantua, wherein Godzilla was to fight Sanda, Gaira, or a new monster of the same name, though no evidence of this has surfaced.
Saperstein's friend, Reuben Bercovitch was to pen a treatment of the tale and the budget for the production had been set at $6 million, which was a very high amount of money for a Godzilla film at the time.
But despite the American involvement, the concept never materialized past the planning stages and Godzilla's career hiatus continued.
- Although the speculated "Godzilla vs. Gargantua" film was never made, Godzilla did ultimately face off with Sanda and Gaira in the comic series Godzilla: Rulers of Earth in 2014.