Modern folklore-focused anime and manga owe a huge debt to the work of 1960s manga Ge Ge Ge no Kitaro's artist and writer Shigeru Mizuki. A second world war veteran, the traumatic amputation of his left arm, due to an air raid explosion, never held back his pre-existing artistic ambitions. An avid researcher of international folklore, he poured his encyclopedic knowledge of the supernatural not only into his wildly influential manga, but also into countless factual tomes – some of which are available in English. Mizuki made his journey to the otherworld in 2015, at the age of 93, leaving an unparalleled legacy that this movie attempts to do justice to, acting as a prequel to the most recent anime adaptation and as an entry point for newcomers.

I'll admit it now – before watching this, I was only familiar with Kitaro, and Mizuki's work in general. Mainly on the strength of Scotland Loves Anime's presenter Jonathan Clements' urgings, in preparation for this review I sought out several volumes of the original manga and episodes of the 2018 TV anime. It appears I am now very much a Mizuki fan, though not necessarily due to this movie.

Oddly, while Ge Ge Ge no Kitaro's TV incarnation is aimed primarily at children (with a theme song that claims it's more fun to be a ghost because school attendance isn't required), Birth of Kitaro is a grim and gritty horror film targeted at an adult audience. It loosely adapts a short manga chapter from 1966, however only uses the most basic of elements from it, crafting a mostly original story, tonally removed from the progenitor TV show. There's even an “uncut” version, released only very recently in Japan, that dials up the already bloody violence even further. Birth of Kitaro has an unusual pedigree: it's written by Hiroyuki Yoshino of Macross Frontier and Dance in the Vampire Bund, while directed by Gō Koga, best known for Precure and Digimon.

We're first subjected to a baffling non-sequitur of a prologue that clumsily attempts to tie into TV show continuity with an appearance from Kitaro and pals in the “modern” day before jarringly segueing into the film's primarily historical setting – it's not a promising start. Most of the action transpires in 1956, during Japan's post-war Showa-era economic recovery. Protagonist Mizuki (who is apparently a stand-in for author Mizuki himself) is an ambitious middle-management businessman who works for the “Imperial Blood Bank,” a company run by the mysterious Ryuga family. When the family head dies, Mizuki is summoned by his boss to the Ryuga's remote mountain village estate to observe the transfer of power to the deceased head's nominated heir. As expected from this genre, events don't exactly proceed according to plan.

It's immediately obvious this village is a strange place – accessible only by dangerous, unmaintained mountain roads, even locals from nearby areas avoid it entirely. Mizuki's arrival is viewed with either novelty (from a village child), interest (from the main female character), or outright hostility (from most of the rest of the cast). His status as an unwelcome outsider is constantly reinforced by various senior Ryuga family members. Once poor Mizuki realizes he's now trapped in a Hinamizawa/Twin Peaks/Royston Vasey-esque situation, it's too late. This section of the film is slow-moving, perhaps as an attempt to build dread, but so many characters involved in random mafia/yakuza movie-style politicking are introduced that it's extremely hard to follow. Eventually, this doesn't matter, as most of the extended cast are murdered horribly anyway. There's a lot of death in Birth of Kitaro, probably unsurprising for a character that fans already know will be born from the corpse of his mother, as the last of his kind. (So, spoilers for the uninitiated… I guess?)

Kitaro himself only barely appears in this prequel – instead, the focus is on the horribly-out-of-his depth Mizuki who finds an ally in the mysterious, white-haired, googly-eyed interloper he named “Gegero”. (The Japanese sound “ge” typically means “creepy” or “icky”, and when repeated like “gegege” it adds emphasis.) Gegero is really Kitaro's father, Medama-oyaji, who is destined to become a talking, disembodied eyeball who resides in Kitaro's empty left eye socket.

Mizuki and Gegero investigate the creepy Ryuga family's secrets to discover the truth of “Substance M,” an experimental blood product marketed by Mizuki's employers. It doesn't take a doctorate in hematology to intuit that the Ryuga are up to no good. Once all of the narrative pieces are in place (and various Ryuga family members are either impaled by trees or otherwise mutilated horrifically), the plot finally rushes headlong into batshit insanity. The final forty minutes or so are a relentless descent into stunningly animated violent hell, with some truly breathtaking action sequences. A particular highlight is Gegero's battle with an army of armored ninja dudes atop a multi-leveled tower, depicted with stylish, fluid, incredibly kinetic animation. A final confrontation centered around a demonic underground tree almost reaches Evangelion-esque levels of surreal metaphysical nonsense.

Birth of Kitaro's ultimate antagonist is somewhat difficult to take seriously (the audience audibly laughed when they revealed themselves), but really isn't that incongruous when viewed in the context of the often goofy manga. I do wonder that if there had been a bit more of that unselfconscious goofiness added to this film, it might have been more entertaining. Without author Mizuki's more whimsical influence, at times Birth of Kitaro feels disappointingly like a more by-the-numbers anime horror without much personality of its own. Its overall seriousness meshes uncomfortably with its more outlandish character designs (such as the Mizuki-accurate cartoony undead, who appear later on), and its overly complex story really doesn't amount to anything by the end, considering the literal mountain of corpses left in the film's wake.

Japanese folklore fans will enjoy the glimpses of yokai, like the water-borne Kappa who briefly appear, while there are plenty of rich cultural references likely to fly over the heads of most Westerners. By the time Kitaro himself arrives, we've seen so much death and destruction that we're almost numb to it, so his birth scene plays as more silly than tragic. That part is adapted more or less panel-for-panel from the original manga, even if the circumstances leading up to his birth are completely different. A bookending flash-forward epilogue re-contextualizes the odd prologue in a genuinely emotionally affecting way – but doesn't make up for the tonal disconnect that makes the opening so off-putting. It would have been better to move the prologue to the end, uniting it with the epilogue.

While I enjoyed the action aspects of Birth of Kitaro, I can't say it works that well as an entry point for new fans. Tonally, it's completely different from both manga and TV shows, plus it's also quite dull and plodding in its first half. Existing fans might get a kick out of this darker, more violent incarnation of the franchise, but I'd recommend newcomers start with the manga or 2018 TV series, which a lot more fun.