Miyamoto Musashi, the peerless swordsman who famously turned up late for duels and invented the two-sword style Niten Ichi-ryu, has inspired much Japanese popular culture (see the Vagabond manga by Takehiko Inoue). Similar to our legendary Robin Hood, the relentless reinventions have led to an understanding of the man more shrouded in fiction than illuminated by fact. Musashi: The Dream of the Last Samurai, a humble documentary, aims to strip away these romantic flourishes and unearth the stark reality beneath. I'm unconvinced it succeeds at its primary objective, but the show does have other virtues.

Mamoru Oshii's (Ghost in the Shell) screenplay argues, in contradiction to much fiction, that Musashi Miyamoto was no Zen-inspired renaissance man but an ambitious warrior hungry for glory as a strategist - the duels that led to his fame as a great swordsman were merely means to that end. Unfortunately, the detail we get as evidence feels flimsy, the examples nitpicky and pedantic. It spends several minutes pointing out that Musashi's renowned The Book of Five Rings merely comprises a loose collection of notes that he wrote over many years, meaning the belief that Musashi wrote it all in one and poetically died the moment he finished is thus nothing more than wish fulfilment. While an interesting clarification, it feeds little into the central argument.

The staid premise is also undermined by the haphazard approach. Rather than a sequential dramatisation, we get a collage of Musashi's life pieced together in fully animated duels, live action panned shots of historical places, and CG sequences of a comical narrator who walks across the screen spouting anecdotes. The last, in particular, features incongruous slapstick humour and overlong digressions like the comparison between Western and Eastern horseback forces. As a result, the documentary will likely end up only one of many interesting interpretations of Musashi as opposed to a thorough overhaul of his image.

But regardless of the show's objective, it manages to highlight just how fascinating the man was. We get a marvellous passage describing the unique fighting style he invented: unlike his contemporaries, who gripped their swords with both hands, Musashi used a long sword in one hand and a shorter in the other, making him not only more flexible, but also faster than his opponents on the battlefield. Somewhat of a polymath (Oshii likes comparing him to Leonardo da Vinci), Musashi also painted a lot and took interest in the science of war and weapons. If this documentary succeeds at anything it is in providing an addictive snapshot of a man who was uniquely ambitious and pushed himself in directions others could only imagine.

Moreover, the documentary translates well for those approaching this subject for the first time, specifically the non-Japanese. While it addresses established arguments about Musashi that most Western fans will have limited knowledge of, it weaves its own interpretation using facts available in fuller detail elsewhere. It can thus function as a summarised introduction even if it fails to peel away ingrained myths or trigger a dramatic schema shift.

A final word regarding the animation - it is a strange jumble of styles that includes grainy, silent movie-esque footage at the start, plenty of 3D computer graphics for the narrator's segments, and action scenes that feature heavy grey tone with splashes of red blood or pink petals. Anyone expecting extravagant sword fights with extra animation flourishes for aesthetic purposes will be disappointed, however. In line with its message, the documentary espouses fanciful touches in order to visually embody Musashi's simple, efficient fighting philosophy.

Musashi: The Dream of the Last Samurai aims to open eyes to a neglected truth regarding Japan's most legendary swordsman but falls short thanks to an unfocused approach and its lack of groundbreaking new evidence (I would argue that reading the Wikipedia page on Musashi would glean a more comprehensive factual treasure in less time than watching the movie). However, it should still appeal to the uninitiated looking for a functional introduction to the subject or established history fanatics crying out for additional hoarding material.