Cops on the edge are a dime a dozen these days, but you will find few as demented or as watchable as James McAvoy in Jon S. Baird's Filth, a rough and hallucinogenic police drama based on a novel by Irvine Walsh, who is best known for Trainspotting. McAvoy is Bruce Robertson, a drunken, coke snorting, bigoted, sadistic cop aiming for a promotion. As one can expect from material based on a book by Walsh, who previously made junkies so funny and glamorous, there's plenty of kinky sex, penis jokes, vomiting, homophobia, racism, nightmare imagery, and dark comedy. It doesn't quite match the crazed euphoria of Trainspotting, and it lacks the hipster punk soundtrack that made that one such a 1990s art house smash, but it has a lot going for it, namely McAvoy's performance. He is a wonder to watch, going from violent to whimsical to pathetic with whipsawing intensity. You'll never be bored by him.
He's funny as he plots to ruin all of the other officers who might compete with him for his upcoming promotion. When an Asian man is brutally murdered by some Scottish punks, Bruce is assigned to head the investigation. He dives in ferociously, just aching to strut his stuff, but also to bust some heads. He freely admits he joined the force because he'd heard how brutal and unforgiving cops could be. A friend asks, "Did you join so you could change things from within?" Bruce sneers, "No, I wanted to be part of it."
Bruce has problems. There's a wife and daughter who may or may not exist. We're never certain if they've died, or if they've abandoned him, of if they existed in the first place. People often ask him how the wife and daughter are doing, yet he's always alone, drinking by himself, watching porn, and making obscene phone calls. His favorite targets for these calls, by the way, is his best friend's wife, which tells you a lot about Bruce. He's a jerk.
If we're in awe of Bruce's sleazy side during the movie's first half, we see in the second half how sad his life has become. Trust me, it's not just the drugs and alcohol that are ruining him. He has a closet full of demons that would impress Norman Bates. At one point he befriends the widow of a man he'd tried to help with CPR, but we can see in Bruce's eyes that he no longer has the mental facilities to be friends with anyone.
The movie is better than it has a right to be. Morbid tales of dead-end cops have been plentiful in recent years, but Welsh's cartoonish slant on Scotland's downtrodden feels as bright as it did two decades ago. The surreal commentary blends with a brutal essay on broken heroes, sexuality, and the small man's futile reach for power. Baird, a 40 year-old Scott who hasn't done much work that we of in America, is a great match for Walsh's vision, pushing the film to its conclusion like a freight train that has jumped the rails but continues to cruise through the air. As Bunty, the subject of Bruce's obscene calls, Shirley Henderson continues to impress as one of current cinema's most endearingly odd ducks, and Jim Broadbent is deliriously weird as Dr. Rossi, the drug enabler who visits Bruce in his dreams and reminds him of his sordid past. Jamie Bell is also amusing as a detective dealing with his own particular shortcomings, and Eddie Marsan finds the perfect notes to play Bruce's sad-sack buddy Bladesey. They're all terrific, in a high-wire act of a film that provides the bad cop genre with a badly needed cocaine bump.