WRITTEN BY: Jon S. Baird
STARRING: James McAvoy, Imogen Poots, Jamie Bell
RATING: 3.5 stars

Sometimes you see a film that unsettles you so much that you are not quite sure what to make of it. Then, the more you dwell on the details, the more you realise just how clever the tale was. That is exactly what happened when I saw Filth. It is a bizarre story about a junkie detective, but the story is shrouded in mystery with layers of details that are only realised upon reflection. While the film is a funny satire, it is also a very dark and intriguing story.

Adapted from a novel by Scottish author Irvine Welsh, Filth's title has a two-fold meaning. First, it is the slang derogatory term for the police in the UK. But also, it is a reference to just how dirty and disgusting the protagonist – who is really more like an antagonist – behaves throughout the film morally, sexually and emotionally. While there were a couple of gaps in the plot that needed more context, the film certainly keeps audiences entertained.

Bruce Robinson (James McAvoy) is a depraved and debauched Edinburgh detective who manipulates his way through the festive season in a bid to gain a promotion and win back the affections of his wife and daughter. If Robinson can solve the murder of a Japanese student everything will work out in his favour. But something is not quite right with Robinson, who was once a good person but has gone down a dark path. As he drinks, snorts and sleeps his way through the investigation, it becomes clear that he has his own personal demons to contend with. Robinson is also a corrupt detective willing to step on top of anyone who gets in his way and belittling those around him, even having an affair with a colleague's wife and humiliating his only true friend.

McAvoy is brilliant as the self-loathing detective. His character is almost completely unlikable, except perhaps in his dealings with a widowed woman and her son, but McAvoy manages to humanise Robinson. McAvoy probably deserves an Oscar nomination for his performance. The supporting cast is also quite good, including Jamie Bell as a junior detective constantly embarrassed by Robinson, and Imogen Poots who plays another rival detective. She has one particularly pivotal confrontation scene with McAvoy.

Filth is a dark murder mystery but the black humour works well. It is confronting in parts, and certainly not a film for everyone. But, if you do not mind going a little out of your comfort zone, you will be rewarded by this film.