On demand: "Beyond the Infinite Two Minutes"

Junta Yamaguchi's Beyond the Infinite Two Minutes qualifies as some or all of the following: a Japanese Primer, a One Cut of the Dead with string theory, a perpetual motion-picture machine, the kind of craziness only a truly adventurous cinema - and a filmmaker compensating for a lack of resources with one blazingly good idea - might think to pull off. It requires some explanation, and thankfully Makoto Ueda's script knows it. The set-up is this: one evening, cafe owner Kato (Kazunari Tosa) locks up his business and takes the flight of stairs to his adjacent flat, only to be confronted - once installed - with his own face on a monitor, apparently broadcasting to his (marginally) younger self from two minutes in the future. The tiniest of rips has opened up in the space-time continuum, in other words, permitting an entirely humdrum and unambitious form of time travel - spanning the distance between closing time (the cafe, downstairs) and the start of the evening (the flat, upstairs), between washing up at night and tucking yourself into bed. It's time travel, but not as the movies have generally known it; it's crap time travel, essentially, barely-worth-the-time travel, which is such an inherently funny idea you may be surprised to learn nobody's troubled to film it before. It will involve Kato conversing with various versions of himself, relaying instructions to those following in his wake, and then trying to reassure everybody else around him that they aren't going out of their minds. Confirmation comes from representatives of the so-called Time and Space Police, who show up dressed like Columbo amid the chaos of the third act and diagnose what exactly has gone awry here: "There's been a reversal of causality." Eureka.

It's enough to make you wonder whether, instead of a script, the film had a whiteboard just out of shot, on which Ueda was busy working out the many permutations of this particular plot; what we're effectively watching is a puzzle being set out, worked through and eventually solved. That process is powered by repetition: repetition of dialogue (the information Kato passes like a baton from one time period to the next), but also repetition of action. With only one location at his disposal, Yamaguchi sets his characters to running up and down between levels of the flat, sometimes carrying the monitors on which their future selves appear, sometimes without. (You feel the cast could have munched their way through the entire contents of the cafe and still lost weight during the shoot.) Yet each repetition carries the film forward, both temporally and narratively. If it helps to simplify - and you will need to get your own head around what's happening here - think of Yamaguchi's film as a linked chain of two-minute units in which the cast react to a trailer of coming attractions (which is really all the future is in the present), and then have ninety seconds or so in which to turn round something they've already witnessed before the next broadcast signal intrusion. This would account for the manic performance style Yamaguchi fosters, although - unlike the actors in any comparable James Cameron or Christopher Nolan endeavours, seemingly crushed by the implications of infinity - this ensemble appears to be having the most tremendous fun, much of which transmits to us. They're like first-time scientists - or little kids - discovering the joy of discovery, and then having to recalibrate their expectations as they realise their future selves are leading them all down a blind alley. (They revel in the gift of foresight.) Ueda and Yamaguchi view this form of time travel not as a crisis, but an opportunity: an opening up of possibilities, for those wide-eyed enough to spot them. You may well end up scratching your head at both the mathematics and logistics involved, or perhaps just wearing a bemused smile; yet I came away chuckling at the film's unmissable ingenuity and energy, and with the added bonus of knowing what Sri Lanka's capital now is. Every day's a school day.

Beyond the Infinite Two Minutes is streaming on All4 until August 15, and available to rent via Prime Video.