No-one is safe from the vileness of James McAvoy’s loathsome cop Bruce Robertson in this dark tale of ambition, not even Robertson himself, as he claws his way towards the coveted role of detective inspector in a grubby Edinburgh. This is the same grotesque larger-than-life world as Irvine Welsh’s hit Trainspotting but without Danny Boyle’s pounding vibe and cool soundtrack.

McAvoy, in a bad suit, rolls up his acting sleeves to play a study in deviousness and perversion and he does it brilliantly with just enough charm and humour in his coke-and-sex-fuelled escapades to keep the audience, if not quite on his side, at least terrifyingly riding along shotgun. Director Jon S. Baird has him grinning into the camera as if issuing a dare to stick with him.

Solving a murder case soon becomes secondary to the points Robertson can score bringing down his fellow colleagues and his preoccupation with rogering every lassie who wanders on screen. Despite his despicableness, Robertson is fun company and there are some deliciously un-PC laughs. With wall-to-wall sex, drugs and violence the R18 rating is well earned. Don’t try sneaking the kids into this one.

Inevitably things start to go badly and the film shifts tone, revealing Robertson as not just a dirty bugger but a real psychopath with destructive hallucinations and a traumatic past. With that the fun drains away and what starts off as a swaggering dark comedy takes a very black turn indeed.

‘Filth’ Movie Times