Like his contemporary David Lynch, David Cronenberg seems to be undergoing a radical shift in direction. But where Lynch’s films are becoming ever more oblique and personal, Cronenberg seems to be burrowing deeper into the heart of the mainstream, a subversive maggot in the multiplex apple. Cronenberg has never exactly been an obscurist, but it always seemed that the films that did serious business – most notably Videodrome and The Fly – did so in spite of, rather than because of his unique and unsettling preoccupations with sexual perversion, human frailty and corporeal decay.

A History of Violence changed all that. Cronenberg’s work had been getting ‘tamer’ for some time – the input sockets in Existenz were the last hint of body horror in his work – but this was his first fully realised shot at the malls of Middle America. You can say what you like about the subversion beneath that film’s surface – the way it plays with genre conventions, tests the limits of an audience’s sympathy, explores the meanings of words like ‘family’ and ‘violence’. Without all that, the film can still be enjoyed as a simple revenge thriller, an update of those gritty Charles Bronson pictures so popular in the mid-70s: indeed, it could be argued that all the lofty critical praise heaped on A History of Violence could just as easily be applied to Death Wish. It’s all just a matter of intention.

Eastern Promises takes the subsurface concerns of A History of Violence and brings them out into the light, bolting them to an even more hysterically entertaining narrative of gangs, guns, prostitution and murder. The film centres around the London branch of a Russian criminal organisation, a world of plush restaurants and grimy suburban slave brothels, where driver Viggo Mortensen is gradually attempting to work his way into the trust and affections of boss Armin Mueller-Stahl, via his alcoholic, sexually ambiguous son Vincent Cassel. Into this hermetic universe stumbles Naomi Watts, as a hospital midwife attempting to translate the incriminating diary of a 14-year-old East European prostitute who died in childbirth.

The first half of the film is surprisingly dour. The screenplay was written by Dirty Pretty Things‘ Stephen Knight, and expands upon many of the themes present in that film: the lives of immigrants in London, their attempts to assimilate or to avoid assimilation, the grim suburban reality of organised crime. Then, for a time, it seems as though Knight’s sensibilities and Cronenberg’s are beginning to go head-to-head, as the bleak authenticity of the script is subtly undermined by the playful genre trickery of Cronenberg’s direction. Reality begins to warp, and the movies gradually intrude. By the time we reach the already infamous Turkish bath scene – a titanic smackdown in which Mortensen brutally slaughters two would-be assassins clad only in a number of intricate prison tattoos – all semblance of veracity has long since flown out the window, and we’re back in Bronson country.

The Turkish bath scene also serves to illustrate Cronenberg’s newest and most playful preoccupation, one of the only major themes in Eastern Promises that was not also present in A History of Violence: the inherent homoeroticism bubbling beneath all such male bonding stories. Using Cassel’s conflicted character as his jumping-off point, Cronenberg examines (and pokes fun at) the seething sexual tension intrinsic to the gangster genre, and to any tight, all-male organisation, on screen or off. These characters’ hatred and fear of women – as evidenced by their treatment of the innocent Watts, as well as their helpless slave-prostitutes – is offset by a desperate need for trust and companionship in their ‘business’ relationships, a confused camaraderie that Cassel expresses physically, by constantly grabbing and touching Mortensen; even, in one scene, openly watching as he takes advantage of a young hooker.

It is these quirky fixations that make Eastern Promises such a joy to watch. In the hands of almost any other director (one can imagine Stephen Frears tackling the script, or even Anthony Minghella), the film would have become a worthy parable of exploitation and integration, further brutalising its characters while softening the bone-crunching violence. But Cronenberg has the ability to see beyond the narrative, to see all the different possibilities inherent in the screenplay – not just a gritty slice-of-life or a rip-roaring gangster thriller, but everything in-between: a family melodrama, a clash of cultures, a test of an audience’s sensibilities, a critique of generic traditions, of middle-class ignorance, of urban disaffection.

The cast are uniformly excellent. Mueller-Stahl reprises his Shine role as the brutal overbearing father, but this time his transgressions go beyond beating his son into statutory rape and murder. Naomi Watts makes the best of a rather thankless role as the hapless suburbanite thrown into a situation she doesn’t understand, but her character only really comes to life in the final stages as she struggles to protect the illegitimate infant. Vincent Cassel’s part seems tailor-made for him – the screwed-up son of a far stronger man, lashing out helplessly at an unforgiving world, losing himself in drink and forbidden fantasies.

But this is Viggo Mortensen’s show, and he commits himself totally. Always a little too earnest, a little too obvious an actor to be taken seriously, Mortensen has been consistently written off in serious critical circles. Eastern Promises is without doubt his career highlight to date, the complete inhabitation of a complex, unforgiving character. His Russian accent is faultless – his face even seems to become more Slavic, his gestures and mannerisms unerringly authentic. He also manages to reflect the growing conflict within the film itself – in the opening scenes he is terse, convincing, frighteningly real. But as the film lets rip, so does Mortensen, becoming an angel of righteous vengeance, expanding to fill the cinema screen.

It’s hard to predict how Eastern Promises will be received when it opens the London Film Festival on October 17. It seems likely that audiences will respond to its heady mix of social realism and celebratory blood-letting, but critics may prove more sceptical. The film walks a fine line, raising some very serious contemporary issues but consistently failing to engage with them, preferring to throw in a new plot twist or another bloody murder. It’s about as subtle as a brick, and perhaps not as deep or thoughtful as it thinks it is. But the fact remains that Eastern Promises is ludicrously entertaining, playful and rebellious, the most consistently enjoyable Cronenberg film in two decades.

Tom Huddleston