[[quoteright:220:http://static.tvtropes.org/pmwiki/pub/images/godzillavmegalon_ja_1475.jpg]]

->"''This is the film most baby-boomers saw in U.S. movie theaters and on TV. Fans had to rely on badly cropped VHS and DVD bootleg copies to enjoy the film thereafter.''"
-->-- Loving script from the back of the first U.S. DVD release.

'''''Godzilla vs. Megalon''''' (''Gojira tai Megaro'') was the 13th entry in the Franchise/{{Godzilla}} series. It was the first film in the series to have someone other than veteran suit performer Haruo Nakajima in the role of Big G, with Shinji Takagi taking over the rubber suit. Interestingly enough, this wasn't going to be a Godzilla film. To cash in on the [[Franchise/UltraSeries Kyodai Hero]] craze, they held a contest in 1972 to make a hero. The winning entry was from an elementary student, who called it Red Arone. Renamed Jet Jaguar, he was set to star in ''Jet Jaguar vs. Megalon'', but he was found not to be able to carry the film. Tomoyuki Tanaka suggested adding Godzilla and Gigan to the film. In order to make up lost time, the film was shot in three weeks and, all in all, production time lasted six months. The film bombed at the Japanese box office, and Jet Jaguar didn't get a series.

For everything its predecessor did wrong, ''Godzilla vs. Megalon'' did it that much worse. Stock footage abounded, the special effects were dodgy at their zenith, and much of the plot was contrived. Nevertheless, the film was the subject of a heavy marketing push, and saw decent theatrical success in the United States, where it was released to cash in on the success of the 1976 ''Film/KingKong'' remake. Megalon was nevertheless well-liked, and a series of video games redeemed Jet Jaguar in the eyes of many fans.

The plot centers around the conflict between an undersea civilization known as Seatopia. Nuclear testing has severely impacted their people, and as revenge against the surface people, they plot to unleash the wrath of their god, Megalon. The Seatopians set up a base by drying out a lake where our ostensible human protagonists, an "inventor" named Goro Ibuki, Goro's younger brother Rokuro and their friend Hiroshi Jinkawa, are trying to relax. They [[DullSurprise don't take it well.]]

The Seatopians attempt to steal Jet Jaguar, a prototype robot, from the inventors. The first attempt, while the robot is still incomplete, is [[HilarityEnsues less than successful]], but the second time sees them capture not only the robot but the three humans. The brothers are sent to be offed, while Jet Jaguar is turned against Japan and used to direct Megalon towards Tokyo.

The heroes escape from the clutches of the Seatopians, and after meeting up with [[RedshirtArmy the always hapless JSDF]], manage to regain control of Jet Jaguar and decide [[GodzillaThreshold to call in Godzilla]] to combat Megalon.

With the guidance of Jet Jaguar removed, Megalon is reduced to flailing around and stomping on a few redshirts. Upon [[OhCrap learning of Jet Jaguar's recapture]], the Seatopians send out a distress call to [[Film/GodzillaVsGigan the Nebula M aliens]], requesting Gigan's assistance, [[BlatantLies which in no way is an excuse to rely overly on stock footage, no sir.]]

Jet Jaguar [[{{Sizeshifter}} grows to]] [[HumongousMecha Kaiju size]] and teams up with Godzilla to fight Megalon and Gigan. Much silliness ensues, including the [[SarcasmMode awe-inspiring]] tail-slide dropkick from Godzilla to Megalon. Eventually, the two villains are repelled and Godzilla shares a victory handshake with Jet Jaguar, who shrinks back down to rejoin his creators. Godzilla, meanwhile, returns to Monster Island, ready for the next adventure...

For the ''Series/MysteryScienceTheater3000'' episode see [[Recap/MysteryScienceTheater3000S02E12GodzillaVsMegalon here]].

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!!Godzilla vs. Megalon provides examples of the following tropes:

* AIIsACrapshoot: Subverted by Jet Jaguar. He is content to be controlled like any robot - until danger is about, at which he becomes a BigDamnHero and takes control of himself.
* ArtisticLicenseHistory: About the [[EenieMeenieMinyMoai Easter Island Statues]] in the InfoDump, one of the main characters states they are 3 million years old ([[FacePalm huh boy]]....).
* TheCameo: Anguirus and Rodan, during the Monster Island scenes.
* CompletelyDifferentTitle / MarketBasedTitle: For some reason, the Spanish translators decided to rename Godzilla and Jet Jaguar for this movie, and it was released in Spain as "Film/{{Gorgo}} y Franchise/{{Superman}} se citan en Tokio" [[MakesJustAsMuchSenseInContext ("Gorgo and Superman meet in Tokyo")]]. Ironically, it and the French version haven't seen release on video.
** Germany got "KingKong – Dämonen aus dem Weltall", or "King Kong - Demons from Space", in which Jet Jaguar was renamed King Kong to most likely cash in on the previous theatrical success of ''Film/KingKongEscapes'' [[note]](which bared the subtitle "Frankenstein's Son" to cash in on the previous success of ''Film/FrankensteinConquersTheWorld...''[[/note]]. Of course, Masato Shimon's song remains intact despite this.
** Italy rechristened it as "Ai Confini Della Realtà", which happens to be the Italian title for ''Franchise/TheTwilightZone''. France's "lost" dubbed version also changed the title, to ''Godzilla 1980''.
* ContestWinnerCameo: Jet Jaguar arose out of a contest held by Creator/{{Toho}} in late 1972.
* DolledUpInstallment: It wasn't going to be a Godzilla movie at first, but Toho had doubts about Jet Jaguar being able to carry the film by himself.
* DumbMuscle: Megalon. Seriously. Removing Jet Jaguar as a guide reduced him to basically nonfunctionality.
* FanServiceExtra: If the watcher can get over how strangely dressed they are the Seatopian dancing women are indeed mostly wearing swim suits and boots.
* ItIsPronouncedTropay: Jet Jaguar's name is always pronounced as the British "Jag-you-ar".
* MacGuffin: Jet Jaguar arguably serves as one for the first two-thirds of the plot, first guiding Megalon and then serving as the means to contact Godzilla.
* OpeningNarration: Ted Thomas' deadpan delivery of "In the first part of 1971, on a small island near the Aleutians..." in the English version is unforgettable and has become a bit of a meme to a few.
* PoorlyDisguisedPilot / StillBornFranchise: This was going to be a vehicle to cash in on ''Series/{{Ultraman}}''. Needless to say, it didn't work.
* RecursiveTranslation: Robert Dunham, who played the Seatopian Leader, read his lines in English on set, was dubbed into Japanese, and then those lines were translated back into English. [[HongKongDub It shows]].
* SizeShifter: Jet Jaguar, for no discernible reason!
* StockFootage: Oh yes.
** The footage of the "nuclear test" at the beginning is from the end of ''Film/EbirahHorrorOfTheDeep''.
** Megalon's powers seemed to be made for this. His lightning attack is an excuse to borrow King Ghidorah's Gravity Beam footage and his Napalm bombs are built for generic explosion scenes.
** The three tanks being blowtorched make their fourth appearance since ''Film/MothraVsGodzilla''.
** One shot of the tanks has [[Film/GodzillaVsGigan King Ghidorah and Gigan approaching in the background]].
* VillainousFriendship: Megalon and Gigan seem to have shades of this in their interactions.