If you have even a passing familiarity with Japanese giant monster cinema, you’re aware of the truly baffling physiology at play. Even the smallest kaiju far exceed the largest real animals on earth in size, to say nothing of their chimeric nature. Godzilla is assembled from three or four different dinosaurs. The cyborg beast known as Gigan is half-chicken and half-chainsaw. Gamera once fought a thing that was equal parts meat cleaver, shark, and hot dog. Into this bewildering field of biodiversity stepped Shoji Ohtomo: writer, manga artist, and most famously, “Dr. Kaiju.”
Shoji Ohtomo made his living designing monsters and sci-fi weapons for Tsuburaya Productions’ numerous kaiju-themed television programs, but it wasn’t just a job for him. He was an early otaku, a devoted fanboy who truly loved monsters in all their rubber-suited glory. In 1966, he released an illustrated encyclopedia known as Kaiju Zukan, where his best-known art appeared: a collection of kaiju anatomical drawings. Taking the form of extremely detailed cross-sections, Dr. Kaiju’s art depicted the muscle, blood, and bone that children around the world imagined just under the foam rubber.
Shoji Ohtomo was a true otaku, though, and his imagination went deeper still. He went so far as to imagine the unique internal organs that gave the monsters their strange powers. It may seem like an uphill battle to explain just how a 200’ turtle can fly and breathe fire, but Dr. Kaiju was absolutely the man for the job. Unfortunately, I don’t have access to a copy of the original Zukan because a) they’re super expensive and b) I can’t read Japanese, so the images below come from Killer Kaiju Monsters, one of my wiser purchases re: giant monster-themed coffee table books. Not only does it have beautiful reproductions of some of Ohtomo’s art, but it also has English translations for the benefit of uncultured gaijin like you and me.

Here’s subterranean monster Telesdon, best known as a recurring foe of the giant alien hero, Ultraman. According to Dr. Kaiju, he’s perfectly adapted to life underground, where he feeds on magma. He’s also got brain matter in his tail and elbows. I’m not exactly sure why, but then again I never finished kaiju college. To his right is Dodongo, the mummy kaiju. This is is one of my favorite designs, and not just because I’m a hopeless mummy fanboy. There’s something about the blessed confluence of draconian fierceness and two-guys-in-a-horse-suit goofiness that makes him a jewel. Shoji Ohtomo has given Dodongo both extending accordion legs and fumes that cause insanity when breathed, an extrapolation that’s half Wacky Racers and half H.P. Lovecraft.

This is Gamera, the RC Cola to Godzilla’s Pepsi. In his first film, Daikaiju Gamera (1965), this monster turtle was depicted gaining sustenance from power plants. Shoji Ohtomo has valiantly attempted to explain this by drawing Gamera with separate stomachs for petroleum, fire, uranium, and coal. Next to him is Gappa, Gappa, Gappa! If Gamera is RC Cola, then Gappa is, like, two liters of lukewarm hot dog water. Don’t get me wrong, I love the Godzilla-meets-cockatoo design, but there’s a reason this thing only got one movie. Ohtomo’s elaborations on this design are suitably bonkers, including a gigantic stomach filled with nothing but octopi and an antenna for receiving transmissions from space. In case Jim Kirk needs to contact a fussy dino-parrot, I guess?

Mystery Science Theater 3000 fans will no doubt recognize Gyaos, Gamera’s shovel-headed nemesis. It’s a titanic vampire bat with weaponized echolocation in the form of a sonic laser. In Dr. Kaiju’s wonderful brain, such a weapon could only come from a giant bone tuning fork the size of a family sedan somewhere in the beast’s gullet. Also, dig that inverted pineapple stomach, whose spiky lining reduces human beings to a bloody slurry for easy digestion.

Bullton is another Ultraman foe. Rather than your standard reptilian giant, he’s a hyper-intelligent brain from the fourth dimension, who uses his near-limitless reality-warping powers to knock over buildings in Tokyo. Sure! According to Dr. Kaiju, his outer shell is made of copper, although I have it on good authority that copper from dimension four looks a lot like foam rubber painted like a Bomb Pop.
Although he died far too young in 1973, Shoji Ohtomo’s legacy is still going strong today. The Internet has given new life to his cross-sections, which are quite popular on tumblr and Pinterest. Today, Ohtomo-esque anatomical drawings of monsters have become something of a genre unto themselves, with examples of The Predator, the Xenomorphs from Alien (1978) and Gizmo from Gremlins (1984) making the rounds online. Now, if you’ll excuse me, I’m off to figure out what the Stay-Puft Marshmallow Man’s liver looks like.