On the incomplete evidence of the films of his that I have managed to see, Kurosawa Kiyoshi is a director whose narratives are in danger of being overthrown by their subtext. It wasn't always the case. His early, sometimes deeply unsettling horror stories were effective precisely because of the potency of the underlying themes, the everyday nature of evil in Cure, the exploration of loss and loneliness in Pulse, and so on. More recently, however, Kurosawa has been less subtle with his subtext and suggestion, notably in the 2003 Doppelganger, which explored issues of duality and the inner self in a manner that leaves little room for viewer speculation or interpretation. It's almost as if the move away from horror has left a void that the thematic underside has leaped up to fill. Bright Future was made shortly before Doppelganger, and like that film has a title that tells you not just what it's about, but what it's really about, if you get my drift.

Yuji Nimura (Jo Odagiri) is a directionless youth who works part-time for a laundry company and has dreams of a bright future brimming with hope and peace. A favour done for his boss leads to an offer of a full-time job for Nimura and his equally lethargic fellow co-worker Mamoru (heart-throb Asano Tadanobu, he of Vital and Survive Style 5+), who keeps a venomous jellyfish as a pet that he is gradually acclimatising to a fresh water existence. An odd bond develops between the two men, with Mamoru offering oblique advice to Nimura on how to focus his life, messages that only hit home after their boss and his family are violently killed and Mamoru confesses to the murders. With Mamoru imprisoned awaiting a possible death sentence, Nimura inherits his experiment with the jellyfish, but one day accidentally lets it loose into the Tokyo sewer system.

All of this may sound like the setup for an environmental thriller, especially if you throw in Mamoru's earlier willingness to let his boss be fatally stung by the jellyfish and Nimura's resentment at his friend's subsequent departure from his job. But it's never played as such, unfolding as a minimalist character drama whose video camerawork and naturalistic performances have an almost documentary feel, but one whose lack of incident and clear intention will require a level of patience that not everyone will be prepared to invest.

With the arrival of Mamoru's father and a turn of events that it would be a bit unfair to reveal here, the focus of the story becomes Nimura's emergence from his bubble of aimless disaffection, a process that Mamoru kick-starts from jail with his increasingly enthusiastic instructions for the care of the jellyfish. With the loss of the animal into the sewer system, the film moves into the realms of the symbolic and the metaphysical, the glowing creature functioning as both a symbol of disenchanted youth and a vessel for a soul in transit. I'm not aware of any basis in traditional Japanese religious or mythological thinking for this, at least beyond the Buddhist notion that reincarnation in animal whose form is decided by the life lived previously as a human.

It's this, and a gestured message that Mamoru sends to Nimura, that prove the film's biggest mixed blessing, with the low-key performances and technical handling sometimes at odds with a say-it-loud approach to elements you'd normally expect to sit quietly beneath the narrative surface. Thus Nimura's life finds direction, Mamoru's father balls him out for not facing up to reality, and the symbolic nature of the jellyfish is pushed home clearly enough for all but the slower viewers to be able to grasp. The resulting narrative only really hangs together in metaphoric terms – strip away the symbolism and you'd be left with a somewhat anaemic tale of a wayward and disaffected youth finding a purpose and direction to his life through learned responsibility. This collision of the unsubtle with the inventive is at its most stark following Nimura's split with Mamoru's father, as his exaggerated disinterest in the office job secured for him by his sister's boyfriend is engagingly shattered when he leads a gang of neon-headphoned young thrill-seekers on a night-time raid into the firm's offices. It's a kinetic sequence that unfortunately concludes in traditionalist fashion with Nimura apologetically learning that maybe the older generation know what they're talking about after all.

Bright Future is a film of interesting ideas and effective moments that do not quite gel into a fully satisfying whole. Kurosawa's almost invisibly observational approach just occasionally drifts into the stylised, with a one-off dip to monochrome and twice-used split screen employed to comment on isolation, companionship, and the closing of the generation gap in a manner that is both economical and a little obvious. The most striking imagery occurs in the later stages in the shape of a river of glowing jellyfish, a sight that invites you to provide your own reading and then emotionally react to it, something that's curiously easy to do. As frustrating as it is intriguing, there's just enough in Bright Future of real interest to make it worth being frustrated by.

Research suggests that Bright Future was shot on 1080/24p high definition video, which surprised me as I'd have sworn that I was looking at mini-DV. Highlights are sometimes seriously burned out and digital noise is often visible. A scene set in Mamoru's cell appears to have been shot in very low light, resulting in the sort of colour drain and dancing digital grain I usually associate with night shooting modes on domestic camcorders. The contrast varies – it's solid enough for much of the film, but every now and then the black levels drop to mid-grey, something that may well have been a conscious decision on Kurosawa's part. Assuming it was shot on high-def then I'm pretty sure we're looking at a transfer that's already been through at least one standards conversion. Within these restrictions this is still very watchable, in part because the video aesthetic works well with the naturalistic performances and the stand-back-and-watch handling of many scenes. Colour is sometimes muted but clear enough when it needs to be, and the detail is often rather good. The framing is 1.78:1 and the picture is anamorphically enhanced.

The usual Tartan trio of Dolby stereo 2.0, Dolby surround 5.1 and DTS surround are on offer. There's not a lot to choose between the Dolby 5.1 and DTS, and both have an edge over the stereo track when it comes to the offbeat score and the location atmospherics, where the surrounds are well used.

None.

Maybe it's just me, as some of the things I found a little obvious about Bright Future have left a few scratching their heads, while others have warmed to its symbolic storytelling. Kurosawa Kiyoshi fans expecting a work as dark and disturbing or as thematically complex as Cure will be in for a bit of a disappointment, but if you can shut your mind to the director's past masterworks (not easy, I know) then there's still some worthwhile material here, and I'd have to say that I enjoyed the film more on the second viewing, when I was freed of expectations for a film that this was never intended to be.