The craziness is all in the idea of this singular Japanese action movie: essentially one marathon battle scene, filmed in a single take, in which a master swordsman takes down several hundred assailants. The execution, as it were, is a triumph of stuntwork, strategy and stamina, but in the watching it gets rather repetitive and wearying. Few but the most hardcore action junkies will really be up for it.

The set-up is quickly dealt with: a clan rallies in the forest around its newly anointed leader, a small boy, in anticipation of an attack. Attack there swiftly comes, in the form of Musashi Miyamoto: real-life master swordsman, 17th-century folk hero, and fixture of Japanese pop culture (Toshiro Mifune played him four times; Kinnosuke Nakamura played him seven times). Here, the role is filled with focused athleticism by local action hero Tak Sakaguchi, although acting abilities play a distant second to sword-swinging skills. The battle progresses through woodlands then into an abandoned village, with Miyamoto dispatching most of his inept assailants with a few efficient strokes: a slash to the neck, a chop to the top of the head, slashes across the belly as they practically hurl themselves into the path of his blade.

It helps that these adversaries come in discrete waves and attack him one by one, and never from behind. It also helps that most of them stumble out of the frame once defeated, thus avoiding a pile-up of dead bodies, or an undersupply of fresh attackers (clearly there are not hundreds of people in the cast). The combat itself is persuasively physical, apart from the regular gouts of CGI blood; the sheer bloody-mindedness of the exercise is admirable (apparently it was filmed nine years ago but only completed recently after a crowdfunding drive). But it’s a case of you’ve seen 50 deaths, you’ve seen them all. Most viewers will tire out long before this Crazy Samurai does.

• Crazy Samurai: 400 vs 1 is released on 5 July on digital platforms.