Rampart

Woody Harrelson doesn't get enough credit for his versatility. He slips effortlessly between genres, whether he's neatly pitching comedy, such as his recent role in Friends With Benefits or playing it straight in films such as The Messenger. Here he inhabits the perma-smoking, dirty cop Dave "Date Rape" Brown to such an extent that Oscar is almost certain to take a long hard look at him. But even though he throws everything into his portrayal, the narrative that surrounds him lacks substance.

The film - scripted from his own story by hard-boiled story veteran James Ellroy - takes its name from the LAPD's real-life Rampart division, which became synonymous with police corruption and brutality in the Nineties. This is very much a one-guy story, however, with Oren Moverman's camera rarely leaving Harrelson.

Dave has a personal credo of justice, without the need for judge or jury, that is as seedy as his nickname - a moniker acquired after he allegedly shot and killed a serial rapist. Somehow managing to dodge the bullet at work due to a lack of evidence - despite the fact that assistant district attorney Joan (Sigourney Weaver, good but largely wasted) seems convinced of his guilt - it is only a matter of time before he oversteps the mark once again.

While Harrelson is compelling as a man in meltdown, everything else fails to convince. It seems highly unlikely that he would have managed to retain his job given his outspoken attitudes and though he ricochets between encounters, including a one-night stand with a lawyer and some dodgy dealings with a former cop, it's all too episodic to care about. His convoluted homelife - he cohabits with two sisters, with each of whom he has a daughter - also lacks coherence and proves little more than a distraction, while later scenes fall back on washed-up cop cliche.

As a character study of a dirty cop in a spiral to oblivion it just about works thanks to Harrelson's commitment, but ultimately the in-your-face style and confusing story stop the emotions from getting truly under your skin.