It lacks the finely honed existential humour of In Bruges, in which Gleeson starred opposite Colin Farrell for director McDonagh's big brother Martin. And the profanity is both less prodigious and less laceratingly witty than in that film. But this debut effort from the man who wrote the screenplay for Heath Ledger's Ned Kelly is an enjoyable, if derivative, comic romp.
The title renders the Irish word "garda" which means "policeman" and that's what Sgt Gerry Boyle (Gleeson) is: a grumpy middle-aged member of the local constabulary in heartbreakingly picturesque Galway.
That his style of policing is unconventional is plain from the first scene in which he lets a speeding car pass his checkpoint so he can pinch the drugs from the pockets of the dead in the crash that inevitably ensues. "I don't think your Mammy will be too pleased about that, now," he quips as he tongues a tab.
It's typical of the appealing one-liners that litter the film but somehow stop it holding together: we are asked to accept that a man of such cynical pragmatism would also think that "only blacks smuggle drugs".
That's what he blurts out when told that a major drug-smuggling ring is planning to use Galway as a drop-off point and he finds himself paired up with FBI agent Wendell Everett (Cheadle), who has been sent over to sort the hick-town cops out. ("We're Irish," he protests, when his superiors object to his offensive questions. "Racism is in our culture.") The Irish white/American black partnership is a buddy-cop set up made in comedy heaven and despite McDonagh's slightly stuttering style, the film becomes more charming as it picks up pace. A particular pleasure is the trio of villains, especially the tinder-dry Strong, whose argument with some cops he's paying off is priceless.