You wouldn't want to mess with Gerry Boyle, Brendan Gleeson's acid-dropping, three-way whoring, pint-slugging Irish cop in the smart new comedy, "The Guard."

County Galway is his beat, and his partner is Wendell Everett (Don Cheadle), a by-the-book G-man matriculated from the finest American universities and sent to Ireland to bust some big-time drug traffickers.

Gleeson has made a career blending seamlessly into ensembles as well as tackling standout supporting parts in movies like "Braveheart" and "Gangs of New York."

He can play working-class or sophisticate with equal dexterity, but he's never more convincing than when he's in his home country of Ireland, as in John Boorman's superb "The General" or here in "The Guard."

Gleeson makes Boyle both lovable and repellent. Always up for a good time on either side of the law, he knows human nature and the difference between transgression and malevolence. Does that make him a bad cop? He's practically a saint compared to the rest of the force, each of them paid to look the other way.

Cheadle's Agent Everett just wants to wrap up the case and go home to his family. He remains blithely unfazed no matter how much Boyle needles him with racist jokes and general boorishness.

First time writer-director John Michael McDonagh conjures two vivid and distinct characters, each of them adroitly complementing the other. Cheadle plays it smart and steady but always a bit irritable, whereas Gleeson is smart and sloppy with a comical bent. They are a misshapen pair in style and countenance, but they're stuck with one another when they discover they're the only ones left who haven't been bribed.

McDonagh is the brother of Martin McDonagh, whose directorial debut "In Bruges" starred Gleeson as a reluctant hit man. And while Martin has gained international acclaim as a filmmaker and as one of this generation's leading playwrights, brother John shows promise but is not yet on the same plain.

The brothers exhibit similar writing styles, and a fondness for the same kinds of characters and locations, but John's uneasy grasp of the medium shows in the film's perfunctory editing as well as its under-lit, grainy photography. Sedentary framing and sluggish pacing hampers the climactic shootout, but the movie's unpredictable story line and vivid characters easily carry the day, making such amateur errors forgivable.

Even with its flaws, "The Guard" marks a killer directorial debut for McDonagh.

Entertaining, funny, profane and unpredictable, his movie reminds us that some crime fighters don't need a cape - just a pint of ale and a pair of brass balls.

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