Lock up: "Wasteman"

Wasteman is the New British Realism mob that gave the world Adolescence shifting their attention from schooling to the prison system. David Jonsson's Taylor is a manslaughter inmate who's been trying to get through his sentence in a narcotics-induced haze; the fug around his head lifts momentarily after he's informed he'll be released on parole - as part of Government plans to relieve overcrowding - if he can stay out of trouble for just a few more weeks. The trouble is he finds this out at precisely the point his own cell becomes overcrowded: his new cellmate Dee (Tom Blyth) is a ne'er-do-well with a neck tattoo who walks on bellowing "The Good Life" in a bloodspattered sweatshirt, turns the pair's notionally shared space into a hectic combination of tuckshop and import-export business, and promptly vows to initiate a turf war with rival dope pushers in a bid to take over the facility entire. In some ways, Dee's not unlike the movie he's in, one of those modestly budgeted Britpics that looks like an expansion of pre-existing TV: muscling past Jimmy McGovern's recent BBC hit Life - and towards the realms of HBO's Oz - with its 18 certificate, Wasteman also retains an air of especially brutal sitcom in describing what proves, for both of these young lags, a most unfortunate (and untimely) flatshare. (It's Porridge with a pool ball in a sock.) Weirdly, it'd even make an unlikely but lively double-bill with last year's crossover hit Pillion, in that it's about two men wrestling - sometimes literally - for position and power. (For motorcycling leathers, swap in drably institutional duds.)

Above all, however, this is that rare kind of Britpic that appears to work for everyone. For those of us looking on, the premise is familiar but inherently dramatic, often tense. Writers Hunter Andrews and Eoin Doran and director Cal McMau get to nudge their way into the industry conversation - and, indeed, last night's BAFTAs - by showing they've absorbed the many recent newspaper exposes of prison life (drug-drop drones! Prohibited cellphone use!); the plot here is by definition self-contained - 90 minutes, much of that time spent on lockdown with bunkbound protagonists - but McMau opens the drama up via mobile-phone footage of what's going on beyond the boys' cell. (Mostly gangland posturing, as it happens, with the occasional grace note: the weariness of a seasoned guard as he's called in from his break by an alarm, the eerie quiet of a riot's aftermath.) The distributors can slap an eyecatching title on all this and sell it to that strain of agitated youth who are permanently cruising cinemas for a bruising. And the actors get to attempt something swaggering and street-tough in close-up, a chance actors generally leap at, given some of the names they were called during their time at theatre school. Casting supremo Kharmel Cochrane calls in all those day players who've been chased away from other auditions for looking like they might steal off with the producer's car, and the leads are (perhaps perversely) a good match. Blyth, who broke through in last year's Plainclothes, captures the mannerisms of a small and not terribly intelligent individual trying to be big and clever: he has to trade in swag because he has nothing else to offer, but he's charismatic company until he turns. And Jonsson, continuing his early-career quest to play every type of role under the sun (Rye Lane, Alien: Nemesis, The Long Walk), gives us a new type of inmate: a nerd, essentially - a scientist incarcerated for getting his sums wrong - who now has to use his brain to keep himself alive. He has a great face for fatigue and suffering, both of which are much in demand here: I hope he can pick up a few cheerier roles along the way, but he could well become this generation's John Hurt.

Wasteman is now playing in selected cinemas.