Review:

Filth (18)

Dir: Jon S Baird

With: James McAvoy, Jamie Bell, Imogen Poots

Runtime: 97 minutes

THERE is a lot to be said for the Ronseal approach to film titles. While one expects the likes of Snakes on a Plane or Attack of the 50 Foot Woman to do exactly what they say on the tin, a roll of the dice is involved when it comes to Eternal Sunshine of the Spotless Mind, say, or Trainspotting, the film that lured many an innocent engine fancier to their cinematic doom.

There is no such chance of confusion with Filth, a comedy drama that doesn't so much want to frighten the horses as see them sectioned under the Mental Health Act, on Valium, and sobbing in group therapy about their first memories as foals.

As the British Board of Film Classification puts it for the avoidance of doubt, Jon S Baird's adaptation of Irvine Welsh's novel "contains very strong language, sex, and hard drug use".

If there is a button to be pressed, be it sexism, misogyny, racism and many another, Filth whacks it with a baseball bat. While this nuclear-strength nihilism leads to initial laughs, the tone soon grows old. Lacking the hand-grenade impact of Trainspotting in the early-Nineties, watching Filth can feel like spending time with teenagers who have just discovered the Sex Pistols and swearing.

Making up for all of that, however, is James McAvoy's blistering performance in the lead, allied to Baird's inspired direction. Both perform a water into wine miracle: McAvoy in turning a scumbag into a fascinating anti-hero, and Baird in mining a sinewy screenplay from Welsh's sprawling, nose-wrinkler of a novel. Anyone who doubts the difference a truly gifted actor can make to a movie should see McAvoy in this.

The Atonement and Last King of Scotland actor plays Detective Sergeant Bruce Robertson, an officer who will never feature on a recruitment poster for Police Scotland. The first sight of McAvoy as Robertson is a shocker, and it only becomes more disturbing as the film progresses. Never mind the eye bags too big to fit on a luggage carousel, or the hair so greasy it would take a saunter through a car wash to get clean; check out that ginger beard. That clash between his brown hair and bright auburn face fuzz announces Robertson as an indisputably Scottish character, a Jekyll and Hyde type.

Robertson, though, is infinitely more Hyde than Jekyll. There is a promotion up for grabs, and Robertson is determined to have it. To this end, the "games" he loves to play with his colleagues will be stepped up: if he can cheat, lie, cuckold or just plain terrorise to get his way, he will. Robertson does not only have trouble at work; through flashbacks we find that his home life is not without its cares either.

So begins Robertson's pre-Christmas elevator plunge into madness, accompanied by the best/worst in festive muzak. Baird handles the back and forth, the leap between dramatic realism and fantasy sequences (the interventions of Jim Broadbent's psychiatrist), with confidence, powering up and down the gears as the road requires. He even manages to give a decent share of the screen time to the rest of a fine cast which includes Jamie Bell as a young cop who looks up to Robertson, Gary Lewis as a cheery old buffer, Eddie Marsan as Robertson's nervous Nellie friend, and John Sessions as the police chief who would rather be writing for the movies.

The women in Filth have a trickier time. The characters played by Kate Dickie and Shirley Henderson fill Robertson's leisure hours in different ways, while Imogen Poots plays Robertson's high flyer colleague. All are subjected to his sexism and general cruelty. While the paint-stripping misogyny displayed by Robertson in the book is toned down, there are still scenes that make for uncomfortable viewing. The picture wants to mock grotesque behaviour while showing it in detail, to shock and shock again, and it can be exhausting to watch.

Sweet relief arrives in the form of the angelic Mary (Joanne Froggatt of Downton Abbey) and her young son. Robertson encounters them in the course of his duties, viewing Mary from the off as a symbol of all that is good and right in a rotten world. She offers the promise of salvation, a chance for him to leave his old ways behind.

Baird has a lot of fun finding out which way Robertson will turn next. Though set in Edinburgh, he makes clever use of locations in Glasgow to show the capital as a place with a rotten underbelly into which Robertson burrows, and he keeps the story going at roller coaster speed, showing no fear. It is a tactic that works for the most part, with the wheels only coming off in the final third.

McAvoy does the rest with a brilliant performance that borders on the possessed. He brings a monster to life and makes him all too human, daring us to feel compassion. The film might revel in the gutter, but McAvoy ensures we cannot resist gazing at the star.