Thanks to a cooler than usual name, his memorably baffling character design, tons of cable television repeats and a handful of Mystery Science Theater 3000 episodes, Gamera remains one of the very few Kaiju to gain his own prominence outside of the Godzilla franchise.
Of course, that still leaves plenty of people out there who have never heard of him. So just to catch everyone up: Gamera is not a giant lizard or an oversized insect but rather a massive turtle. For added menace, he has upward pointing tusks. For added lulz, he flies by spinning like a top.
Gamera's first film run, designated the "Showa" series, consists of seven increasingly kid-friendly films and one clip show (more or less). Like a lot of Kaiju films, the Showa Gamera series showcases a certain goofy charm that negates its significant shortcomings. The films are easy to make fun of but also kind of special. If you're already predisposed to Kaiju movies, it's hard not to get excited about something like Gamera's foe, Guiron, a kind of shark Kaiju whose entire head is one giant sword (and who, by the way, appears to have a modern counterpart in Pacific Rim's Knifehead).
The last real film of the Showa series came with 1971's Gamera Vs. Zigra. But in 1995, Gamera was revived with a great trio of films known as the Heisei Trilogy. First came Gamera: Guardian Of The Universe, followed the next year by Gamera 2: Attack Of Legion, and concluding with 1999's Gamera 3: Awakening Of Irys (sometimes referred to as Revenge Of Iris). All three films were directed by Shusuke Kaneko, who would go on to direct two Death Note films as well as 2001's Godzilla, Mothra, And King Ghidorah: Giant Monsters All-Out Attack.
Being a Kaiju fan means sitting through a lot of poorly made, often ponderous and always cost-effective human scenes when all you really came for is the giant monster fighting action. Each Kaiju film must navigate a tricky ratio of human to monster screen time. If the monster stuff is really special, you can afford more scenes spent among boring humans. If the monster fights are lame, you'd better at least have a lot of them. The magical combo rests at about half and half, especially if the filmmakers found a way to make the human stuff interesting. The best I've ever seen in this regard is War Of The Gargantuas, which manages to be entertaining no matter what kind of scene you're watching.
The films in Gamera's Heisei Trilogy devote way too much time to human storylines, but it's worth it for a few reasons. For one, each film really tries to go deep into Gamera mythology, and while slow going, much of it is pretty interesting. For instance, the third film opens with the surprise discovery of an underwater graveyard filled with the skeletons of previous Gameras. This bit is indicative of the bigger ideas at play here. The Gamera graveyard never really pays off the way you want it to, but it's a jaw-dropping Kaiju moment regardless, the likes of which no Godzilla film has yet approached.
This more serious tone does occasionally stumble, but even this is part of the fun. When an onlooker names the second film's villain Legion by starkly quoting biblical verse, it's hard not to guffaw a bit. The same goes for the way the film's credits isolate the second Katakana character in Gamera's name, which kind of looks like a drunken letter "T," so that it briefly resembles a martyr's cross before the rest of his name shows up.
It's also easier to pay attention to all the human scenes because this is a real trilogy, not just three separate films unified by style and decade. Not only do all three entries have the same director, but they all star Yukijiro Hotaru, Shinobu Nakayama and Ayako Fujitani (Steven Seagal's daughter!) in roles that grow in importance from one film to the next (or diminish, in Yukijiro Hotaru's case). You could sit down and watch Gamera 3: Awakening Of Irys without knowing anything about the previous two, but it would barely make any sense, and you'd be missing out on a medium amount of world building.
But the main reason the human scenes are worth sitting through is the same reason all Kaiju human scenes are worth sitting through: It's just the price you must pay to get to the fights. And Gamera's fights are absurdly great. One very important detail that sets Gamera films apart from Godzilla films is their dedication to Kaiju gore. This is true of both the Showa and Heisei Gamera series. The guy bleeds a lot. To give you an idea of how awesome these films can get, in Awakening Of Irys, Gamera at one point finds himself unable to defend himself because his hand has been pinned to a wall. So he just rips it off and finishes the fight with one hand figuratively tied behind his back. Godzilla never did anything like that.
These movies get down and dirty, and that more than any other reason is why you should watch them. If Godzilla is the ubiquitous standard-bearing Harry Potter of Kaiju and Mothra is the saccharine but stiff Hermione Granger, then Gamera must be Kaiju's Ron Weasley, the poor, redheaded kid with a filthy mouth and ratty clothes who knows how to take a beating.
Over-the-top violence and crazy origins help elevate Gamera's villains beyond just regular old Kaiju, which is kind of what they look like. In Gamera: Guardian Of The Universe, Gamera fights the Gyaos, who look like little more than Rodan ripoffs. But while the Gyaos are physically unimaginative villains, their unexpected meanness demands they be taken seriously. Gamera spends the next film fighting Legion, a bunch of crab Kaiju. You want to roll your eyes at them, but when hundreds cover Gamera like a bunch of army ants, the imagery is kind of sickening and awesome. As the film goes on, all the little alien crabs combine into one main foe whom Gamera blows up (after ripping off one of her horns). The third film gives this Gamera trilogy its greatest Kaiju villain in Irys, a kind of a bi-pedal dragon Kaiju with fluid-sucking tentacles and lots of sharp spikes all over.
On top of all the tough fighting, Gamera also has to contend with the Japanese Self-Defense Forces. These knuckleheads go back and forth on whether or not Gamera is friend or foe. As a result, the trilogy features several instances where Gamera needs to go chase some villainous Kaiju but can't because the JSDF is shooting him down with missiles. This has the odd but extremely pleasing effect of turning Gamera into not just a genuine hero but a harried one as well. Impeded by the very people he's trying to defend, Gamera puts off an almost John McClane level of exasperation, all without changing his facial expression. It's great.
The 1990s were impressive years for Kaiju films. Filmmakers had generations of practical special effect techniques to use and improve upon. Kaiju effects were subtly enriched by rather than dependent on CGI. You can tell the difference just by comparing Gamera movies. The first series is limited but fun. The Heisei Trilogy looks just right. And the only millennial effort thus far, 2006's Gamera The Brave looks like a goofy, weightless cartoon.
Continuity is nothing new to Kaiju, but if you're looking for a fun, narratively concentrated trilogy of films to marathon in one afternoon, you can't do much better than the Heisei Gamera Trilogy. The three films offer great looking, surprisingly violent Kaiju action, a weirdly relatable hero and an overall story arc that manages to be more epic in scope than you might expect.