Neds, Peter Mullan, 124 mins (18)

Bad-education drama Neds is only the third feature directed in 14 years by Peter Mullan, who – if he weren't so visible as an actor – could have drummed himself a nice bit of mystique as an Elusive Pimpernel of film-making, Scotland's own Terrence Malick.

Not that Mullan, I suspect, cares for anything as vaporous as mystique, or nostalgia. A picaresque, quasi-autobiographical evocation of a 1970s Glasgow adolescence, Neds – if not quite in the league of that coming-of-age classic – could be described as a Scottish 400 Blows plus a few razor slashings and a headbutt or two.

We meet protagonist John McGill (played aged 10 by Gregg Forrest) as a serious-minded altar boy bound for success – then caught reading a book by bully Canta (Gary Milligan), who vows to make his life a misery. But John's big brother Benny (Joe Szula) is a feared hard man, who promptly gives Canta a summary warning involving two bottles strung round his neck.

When John starts his new school, he's put down a grade because of his brother's reputation. Everyone insists he's bad news, so he decides to conform to expectation. At 14, John (now Conor McCarron) joins a gang and joins in local rumbles, some murderously brutal. Our sympathies are with the misunderstood lad, but Mullan makes a point of testing them, notably when John commits a horrific act of violence, then goes straight back to an interrupted snog.

Neds – reputedly standing for "Non-Educated Delinquents" – is a film with plenty on its plate. It's about teenage masculinity, and about a moribund teaching system dedicated to grinding down individuality through systematic humiliation. The school scenes offer terrific, sardonic comedy, picturing a cadre of sour-souled, chalk-fingered, instinctively punitive men: Steven Robertson stands out as a pompous Latin master who believes that when a pupil excels, it's a special opportunity to embarrass him. And Gary Lewis has a relishable cameo as a teacher who greets latecomers with the bitterly sarcastic, mock-cordial offer of a piggyback.

The film is also very evocative of the 1970s, a rare British example of getting that decade right. There are a few sparely-used knee-jerk signifiers of the era, what you might call generically "Curly Wurlys", such as a TV clip Hector's House and assorted pop nudges. I'm not sure it works in the fight scene, but full marks for choosing "Cheek to Cheek", as crooned by Glasgow's terrifying pre-punk hero Alex Harvey. Mullan presents a picture of Seventies fashion that's entirely without the usual cartoonishness. If a boy saunters on in Bowie brush cut and platforms, it's not for easy laughs, but because this is his battledress – those billowing Oxford bags have a knife in the waistband.

Mullan's teenage unknowns look the part and the period – from 14-going-on-40 toughs to baby-faced swaggerers (Christopher Wallace stands out as manic squirt Wee T). An outstanding discovery, McCarron conveys the range of John's emotions while keeping so much hidden beneath an apple-cheeked exterior – from barely-concealed fear to bullish strut, and then sullen, suicidal desperation. When John eventually strides bare-chested into the enemy camp, knives taped to his wrists – intent on martyrdom or massacre – he still conveys an alarming vulnerability.

There's no sentimentality in depicting the gangs' roaring esprit de corps, but the predominantly male frame of reference is a limitation: the girls have little to do but sway glumly round their handbags. It may be an accurate reflection of the sexual perspective of John's generation, but it feels strange in a film of today. John's older sister (Marianna Palka), who's made a career in the United States, is presumably there to redress the balance, but never seems integral to the whole.

The film is made with vision and vigour – its realism hard-edged but heightened, with Roman Osin's photography capturing both everyday drabness and a period glow, tinged with the chemically rosy hues of old Kodak snaps. Mullan sometimes misses the mark – a nightmare scrap with Jesus might have worked better if it hadn't been soundtracked to The New Seekers at their jolliest. And the film ends on an awkward note, with a surreal coda in a safari park. Mullan's own performance as John's drunken, abject father – ineffectually bellowing from behind clerkish spectacles – is poignant, but nearly unbalances the film's delicate economy.

Still, these flaws and excesses all add to the sense of bristling ambition that's so rare in British cinema right now. It may lack the sober, finished economy of Mullan's heart-wrenching, female-centred The Magdalene Sisters, but it's a bracing antidote to UK cinema's usual polarities of half-cocked populism and manicured politeness. If we've all done tugging our forelocks before The King's Speech, here's something rather stronger and, for my money, more compelling.

Next Week:

Jonathan Romney peruses visions of the beyond from Clint Eastwood and Alejandro Gonzalez Iñarritu

Film Choice

Ryan Gosling and Michelle Williams in a tarnished romance in Blue Valentine, a bittersweet drama that's a welcome antidote to the romcom epidemic. London's Cine Lumiere is showing Isabelle Czajka's Living On Love Alone, a tart tragicomedy about the hell of working life and the call of rebellion. French up-and-comer Anais Demoustier stars.