Colin Farrell and Brendan Gleeson star in "In Bruges."

Playwright Martin McDonagh breathes unabashedly obscene, new life into the overly familiar mismatched-buddy formula with "In Bruges," a comedy about hit men sent into hiding in the quaint Belgian city.

Colin Farrell and Brendan Gleeson are clearly having a blast reveling in the rapid-fire rhythms of McDonagh's politically incorrect dialogue, their deadly profession a sharp contrast with their fairy-tale surroundings. Ralph Fiennes tears it up, too, as their brash boss.

Farrell, doing some of the best work of his uneven career, is like an anxious puppy as Ray, looking around nervously and complaining nonstop about his desire to be somewhere, anywhere else. Gleeson, meanwhile, is the sweetly calm father figure as Ken, who's tickled to be in Bruges and insistent on traveling its charming canals and taking in the medieval sights.

They play off each other with ease and relish, especially as the situations they find themselves in become increasingly absurd.

A heralded British playwright of Irish descent who's had hits on the Broadway and London stages ("The Lieutenant of Inishmore" is currently in production at the Phoenix Theatre, and "The Beauty Queen of Leenane"), McDonagh won an Oscar in 2006 for his live-action short "Six Shooter".

"In Bruges" knocks you over with its initial energy, then turns intriguingly darker as Ray finds himself incapable of escaping the guilt he feels over the hit that went horribly wrong -- his first and last -- which forced him and his partner, Ken, to lie low.

"In Bruges" is a wildly imperfect feature debut, but it makes you curious to see what else McDonagh has to offer.

Christy Lemire / Associated Press