“The Last Right” is an Irish comedy of no great consequence and endless charm. A road picture with an engaging cast traversing the length of Ireland wrapped in wintry grey, it plays as cinematic comfort food — cute people on a daft quest muttering those three words that cover the full breadth of Irish irritation.

“Fer feck’s SAKE!”

The first character to use it has his reasons. Daniel (Michiel Huisman of “Game of Thrones”) is an expat, a New York lawyer just trying to fly home, but not “for the Christmas,” as his seatmate, the ancient Padraig (Jim Norton) speculates. No. He’s going home to bury his mother.

But as he’s named Murphy and Padraig’s named Murphy, Padraig talks Daniel’s ear off.

“What’re the chances?” “Pretty high.” Even the pilot making the landing announcement is Captain “Murphy.” Padraig’s on a funeral mission too, bringing his brother “in the luggage” home for a proper burial, “the last right” thing he can do by him.

Padraig impulsively jots down Daniel as “next of kin” on his customs card, and promptly dies in his seat. And there’s no convincing the “Fer feck’s SAKE” shouting stewardesses or customs or the local Garda officer “in training” that the old man screwed up.

Daniel’s got his own issues. He’s got deadlines. Bury mother Sarah, fetch brother Louis (Samuel Bottomley) and jet back to New York.

But Louis is autistic, 18 or so and locked into his routines. He doesn’t want to leave. He insists “Sarah” wouldn’t have left the old man with no one to claim him at the airport. And really, Daniel would be doing Ireland a favor, tidying up this “next of kin ” business by delivering the body for a double funeral presided over by Father Reilly (Brian Cox), who knew both brothers.

Where was Padraig headed? To Rathlin Island. Fine. Body in a cardboard coffin, stick it in — or on — the car, and we’ll run it up there. But Rathlin Island is in NORTHERN Ireland. Damned if the Garda in charge (Colm Meaney, perfect) doesn’t foresee “an international INCIDENT, fer feck’s sake!” He’s got to stop them.

And then there’s the helpful sister of the mortician, who needs to tidy up an untidy love affair with a man in Ballyskenagh. Mary (Niamh Algar) will “help wit’th’drivin'” and perhaps with Louis, whom she knows, if she can just hitch a lift.

A couple of “fer feck’s SAKES” later, they’re off. What could go wrong?

Huisman isn’t a natural at comedy, but does a fine job of staying out of the way of the laughs here.

Algar, quintessentially Irish and at home in dramas (TV’s “The Virtues”) and comedy, turns on the salty, disarming charm here. She’s got the “Minnie Driver role,” a little Irish contrast to the wound-too-tight New Yorker. Making jokes about the “Rain Man” nature of the journey, more tolerant of Louis’ many phobias and tics, can Mary keep the peace long enough for them to fulfill their sacred quest? Maybe keep the Garda at bay, because they’re giving chase?

And “help wit’th’drivin’?” Oh, you know how these things work.

As we learn more about the grey scale of autism, movies and TV grow more fast and loose with such characterizations. Louis is more Sheldon Cooper than “Rain Man,” and that makes his place “on the spectrum” play more as a convenient screenplay affectation. It blows up at the worst possible moments — “Dark soon. BED time!” — or the funniest.

Louis has a “song of the day” that he downloads and plays to death. For this trip with his self-absorbed brother, he’s picked Denis Leary’s greatest hit.

Mishaps and miscommunications abound as our trio tries to trek north, with many a “fer feck’s SAKE” at every turn. I’m guessing the phrase pops up 77 times here, and it’s a laugh line every damned time it does.

Cox and Meaney add a wee twinkle here, a touch of “crusty” there.

And contrived as it often seems, “The Last Right” is just unpredictable enough to pass muster, just cute enough to charm and just romantic enough to get by.

MPA Rating: unrated, adult situations, smoking, lots of profanity

Cast: Michiel Huisman, Niamh Algar, Samuel Bottomley, Colm Meaney and Brian Cox.

Credits: Scripted and directed by Aoife Crehan. A Level 33 release.

Running time: 1:43