From just about any angle you want to approach it, 1975's Terror of Mechagodzilla is heavy with Significance for the Godzilla franchise. For one thing, with 28 total Japanese movies and one semi-official American production released in the monster's first 59 years, this fifteenth film finds us at the numerical halfway point. But that's for the accountants. More importantly for the movie itself, it was the first Godzilla film directed by the franchise's original director, Honda Ishirō, since All Monsters Attack, six years earlier; and where Honda went, composer Ifukube Akira followed, and between the two of them, they made this matinee-budget sci-fi thriller about invading aliens and giant seahorses the most grave and deliberate and consequential Godzilla film in a decade, since at least Ghidorah, the Three-Headed Monster.

I do not know exactly what drove Toho to snatch Honda out of his effective retirement from movies (he hadn't made a feature since Space Amoeba in 1970, spending the intervening years in television; he would make no more after this, save for the rumors that he shadow-directed a sequence or two of Dreams for an ailing Kurosawa Akira), but I have a suspicion. With the previous year's Godzilla vs. Mechagodzilla having spectacularly reversed the series' slide at the box office to be the biggest Godzilla picture in Japan since the '70s, I wonder if the suits were ready to free the King of the Monsters from his kiddie-flick hell, and bringing back Honda - no lover of the franchise's juvenile turn in the back half of the '60s and onward - was a means of triggering that shift. If so, it didn't work, and perhaps even backfired: Terror of Mechagodzilla remains, four decades and so many movies later, the least-attended of all Godzilla films in Japan.

And that sets up the most Significant thing of all: this was the last movie in the first phase of Godzilla films, so-called in English the Showa Era of daikaiju eiga, with its box office failure on top of the visibly largest budget a Godzilla film had boasted in years, sending the monster into hibernation that lasted nine years. In a wholly predictable irony, the film that managed to do what so many tanks, aliens, giant beasts, and alien robots had not done, finally killing Godzilla off, is kind of terrific and certainly better than its fate. It's easily the best of the '70s films, I would almost say, though that bar is low enough that I'd like to find something a little bit more meaningful to use as a comparative. At any rate, its grimness makes for a fantastic change, even if it did doom it with audiences expecting more comic romps (in America, it was butchered to the point of incomprehensibility to remove the most violent moments, in a feeble attempt to align it more with the other '70s films).

Proving that movie executives are the same the world over, at all points in history, this follow-up to the financial hit Godzilla vs. Mechagodzilla doubles as the series's very first direct sequel, starting of course with its title. And with the stock footage recap of the battles between the title figures underneath the opening credits. The film establishes relatively early on that the alien race from the third planet of the black hole, introduced last time, are back with their plans for Earthly domination still intact, and their secret identity as shape-shifting gorillas happily ignored (we learn now that their anxiety to take over our planet owes to their homeworld's imminent demise, falling into the black hole; a fine example of screenwriter Takayama Yukiko's knack for taking some of the stupidity in the last film and making something useful of it). Once again, they plan to use Mechagodzilla to do the job, though the robot is in bad shape, after having been beaten to scrap and dumped at the bottom of the ocean.

Even before we learn of the aliens' return, though, the film has already introduced us to the crew of a doomed submarine hunting for the same scrapped mega-robot, finding instead a creature everyone calls a dinosaur, though it's plainly more of a skyscraper-sized seahorse with legs: this is the deadly Titanosaurus, a being predicted years ago by fringe genius scientist Dr. Mafune Shinzo. When INTERPOL agent Murakoshi Jiro (Uchida Katsumasa), investigating the sub's destruction, goes to the reclusive Mafune's home, he finds only the scientist's daughter Katsura (Ai Tomoko), who informs Murakoshi and marine biologist Ichinose Akira (Sasaki Katsuhiko) that her father has been dead for five years. Of course he hasn't; he's alive and well, if thoroughly insane now, and played by series mainstay Hirata Akihiko in what would prove to be his last performance for the franchise; he died shortly before production started on the eventual reboot.

Among Mafune's bold, far-out ideas to have come true, he had devised a means to control animals. So it is he, in fact, driving Titanosaurus, at the behest of Mugal (Mutsumi Goro), head of the alien invasion force. The combined forces of Titanosaurus and Mechagodzilla (as soon as it's up and running) will surely be too much for humanity to survive, but humanity luckily has a trump card: Ichinose and Katsura fall in love, and she begins to subtly undermine her father and the aliens' plot. It just so happens that Katsura is also a cyborg, saved from death by alien technology, which makes it awfully easy to reprogram her into a more docile and far more dangerous state when things start to get too out of hand, though.

Hey, so what name didn't crop in all of that? Godzilla! If there is one unanswerable flaw with Terror of Mechagodzilla, it's that the film takes ages and ages for its presumptive main attraction to show up. Indeed, kaiju action as a whole is at a terribly low ebb in the film, though effects director Nakano Teruyoshi makes up for it with what are undoubtedly the best monster sequences in any Toho kaiju eiga to that point after the death of Tsuburaya Eiji. They are grand, massively physical fights, with the three suit actors (Kawai Toru as Godzilla, Nimiamoto Katsumi as Titanosaurus, and Mori Ise as Mechagodzilla; only the last of these men had performed in a suit before this film), scrambling and brawling with each other in desperate, brutal moves, not really like animals, but also not like the cartoon wrestlers that had dominated the last decade of films in the series, as Ifukube's thunderous music (largely reiterations of themes he'd already introduced, but it's a glorious return to form) increases the sense of scope and drama, and the action takes place in slow-motion, an easy trick to add weight and impact that the series had ignored for years. Mechagodzilla and Titanosaurus are both pretty fantastic-looking creatures, too, with the former wearing its scuffs and stains to look far more plausible than last time, the latter a wonderful mixture of fairy tale monster horror and fever-dream paleontology. Godzilla is... better than Godzilla vs. Megalon and Godzilla vs. Mechagodzilla, the two times that suit had been trotted out before. His eyebrows are heavier, so he looks meaner. It's still a really shitty suit with dorsal spines that look like throw pillows.

The point being, though, the kaiju fights, however excellent, are a very small element of the whole. And while that's never a "good" thing, it was never such a little problem as it is in a film whose story is treated with uncharacteristic seriousness by the filmmakers and actors alike, despite the silly bits all over. Time away from the genre did Honda world of a good: this is, bluntly, his best-directed daikaiju eiga since Mothra vs. Godzilla. He treats events with sincerity and focus, he seriously considers the emotional ramifications of the story and characters, and the performances follow suit: Ai in particular is quite tremendous, playing the theoretically absurd role of a robot-woman in love with great depth and tenderness, making for the single-best human character in a Godzilla film in... Christ, a long time. It's enough to make that character's ultimate fate (rendered incoherent in the American cut) truly heartbreaking. A word that hasn't applied to a Godzilla film since he was still a metaphor for Japanese post-nuclear trauma back in '54.

Am I necessarily pleased that Terror of Mechagodzilla has so little of either terror or Mechagodzilla, and so much of humans, aliens and cyborgs going through their surprisingly tragic, downbeat motions? Well, no. But that story is so astronomically superior to all of the largely similar "invading aliens controlling giant monsters" plots in and out of the genre over the previous ten years that it's easy to be forgiving. It is not merely a fun and exciting movie, it is an interesting one, with a plot that is compelling to follow, and while that's never the reason we come to a Godzilla film, it's spectacularly pleasing when one turns out that way.