Jet Jaguar was the earliest example of a fan-service in a Godzilla film, the result of a contest Toho had in mid-to-late 1972 for children to come up with a new hero for them to use (to capitalize on the many tokusatsu and anime superhero and super robot shows that were all the rage at the time). The winner of the contest was an elementary school student, who submitted the drawing of a robot called Red Arone, which superficially resembled both Ultraman and "TranZor Z"
(1972) (both of which were very popular at the time). The robot was renamed "Jet Jaguar" and was set to star in a film vehicle for him, titled "Jet Jaguar vs. Megalon," which pitted him against Megalon (a previously unused Godzilla enemy design). However, Toho figured Jet Jaguar would not be able to carry the film on his own, either in screen appearance or marketing value (which was very important to Toho), so they shut the project down during pre-production after doing some tests and storyboards. Less than a month later, screenwriter Shin'ichi Sekizawa
was called in to rewrite the script to add Godzilla and Gigan, providing more marquee value (especially since Godzilla was still very popular with children). After revised pre-production, shooting took a hasty three weeks to make up for lost production time. Due to this delay, the total production time, from planning to finish, was six months.See more