Slight returns: "West Is West"

This here's a late one in coming. East is East - adapted by Ayub Khan Din from his own stageplay, and directed by Damien O'Donnell - was one of the biggest homegrown hits of 1999, capping a decade of unusually buoyant British filmmaking (Brassed Off, Trainspotting, The Full Monty, Lock, Stock...) and, perhaps more pertinently, a decade in which Asian films and culture had themselves begun to edge into the UK mainstream, whether in the form of those Bollywood extravaganzas breaking the box-office Top 10 on a regular basis, or Talvin Singh's late-90s Mercury Music Prize triumph.

Twelve years on, and - perhaps inspired by the success of Slumdog Millionaire - Khan Din has attempted a sequel, West is West, which emerges into a markedly gloomier climate, both financially and socially. The opening credits suggest the producers have effectively had to flip channels in order to get this one off the ground (West is a BBC Films production, where East was backed by Film4's now-withered distribution arm), and the release date rather infelicitously coincides with the Prime Minister's recent insistence that multiculturalism - of a type both films enthusiastically embrace - has failed as a policy within the UK. I'm genuinely intrigued to see how the film will perform - more so, perhaps, than I was watching the film itself.

Khan Din here explores an obvious trajectory left open at the end of the earlier film, dispatching George Khan (Om Puri) - chip shop king of 1970s Salford, who spent much of East decrying all things English - back to his native Pakistan in search of a bride for shy eldest son Maneer (Emil Marwa). Part of the writer's project appears to be to redress any slight the first film may have aimed at its lead character, paring back the edges of Puri's petty tyrant to reveal something more rounded, affectionate, even - and thus inadvertently conforming to the unwritten sequel rule that all compelling monsters must, with repetition, become pale shadows of their former selves.

In this, at least, Khan Din is aided by a set of commendable performances. Whatever gravity West possesses derives almost entirely from Puri's ability to eke out something thoughtful and human from the modest material set in front of him. There's a find, too, in young Aqib Khan, bristling away as Sajid, the tearaway youngest George has dragged along with him to show him his roots: his "fuck off"s have the uncoachable ring of authenticity. The opening Salford act, trying to prod our memories, offers a one-scene bit for Jimi Mistry's Tony, a fixture of the first film; something more substantial from Linda Bassett as the second Mrs. Khan; and a nice turn from Robert Pugh as the headmaster who was stationed in Rawalpindi during the War, and thus feels compelled to sprinkle his speech with gobbets of condescending Urdu.

But there's only so long West can rest upon its acting laurels, and the midsection betrays the fact there was no pressing reason to bring these characters back, save that they struck a chord once upon a time, and that Khan Din has Valuable Life Lessons to teach them all. Once returned to Pakistan, George has to learn to do right by his neglected first wife (Ila Arun): this he does by building a house in her backyard that forms the BBC Films idea of the Taj Mahal, and stands, come the end credits, as a waste of everybody's time and effort. Sajid, meanwhile, learns to respect his roots and elders, rather undermining the message of the first film, where it was precisely these elements that were seen as holding the younger generation back. (Where East was a very New Labour project, West is in every sense conservative.)

By the time Bassett and her comedy sidekick have themselves arrived in the village ("I told you crimplene was a bad choice to travel in"), the film's become mired in sitcom territory - a man caught between two wives - a feeling hardly dispelled by TV veteran Andy De Emmony's unassuming presence behind the camera. Khan Din's default mode of writing remains broad, below-the-waist comedy (there's much consternation over shitting in a field, and a mix-up over the word "bullocks") interspersed with jolting instances in which characters at loggerheads go at one another in small, scarcely cinematic rooms.

Sometimes, the tactic works: though it feels convenient indeed to have the two Mrs. Khans thrown together in the one mud hut by a sandstorm, the actresses transcend the tweeness of Khan Din's conceit (with neither able to understand the other, they come to communicate through gestures of the heart) to arrive at something at least touching, if not fully moving. More often, it just comes over as crude, as with the supporting Pakistani characters, whose English is dotted with "bloody" every other word. At any rate, the element of surprise - the immediacy that might still have been there in a sequel two, three, even five years on from the original - has long since gone. The film is good-natured but unadventurous: maybe audiences will be more forgiving.

West is West opens nationwide from Friday.