Wild Mountain Thyme, review: Jamie Dornan’s awful romcom is an insult to the Irish

• Dir: John Patrick Shanley. Starring: Jamie Dornan, Emily Blunt, Christopher Walken, Jon Hamm, Lydia McGuinness, Danielle Ryan. 12A cert, 104 mins

For all those who groused that this year’s Oscar titles were too weighty and severe for their own good, here is the antidote: a film so frivolous and twee I felt as if my brain were leaking out of my nostrils as I watched.

Expanded by John Patrick Shanley from his 2014 play Outside Mullingar, Wild Mountain Thyme is a romantic comedy about a man and a woman who were raised on neighbouring farms somewhere inside an advert for the Irish Tourist Board, in which the green in every field and hillside has been cranked up to a queasy hue.

Their names are Anthony (Jamie Dornan) and Rosemary (Emily Blunt), and both are young, attractive, well turned-out and seem compatibly eccentric – a change from the play, in which the leads were both unprepossessing 40-somethings who had spent their entire adult lives on the shelf. Here, it’s hard to fathom why the pair aren’t already an item: they’ve obviously been yearning for one another for years and the usual romcom obstacles – social differences, family objections and so on – are conspicuous by their absence. (The best hitch the film comes up with is a minor childhood squabble that any normal person would have got over as soon as puberty struck.)

Indeed, when Anthony finally explains what has been troubling him his whole life, it makes so little sense that the viewer is left wondering if the character is in fact talking figuratively – extremely figuratively – or, in an unexpected last-act twist, has turned out to be a lunatic. Perhaps this is what Anthony’s elderly father (Christopher Walken) has picked up on when he announces early in the film that he's considering writing his son out of his will and selling the farm to Anthony’s strapping American cousin (Jon Hamm) instead.

To say that Anthony and Rosemary behave like characters in a play might sound like a statement of the obvious, but there really is no trace of recognisable human behaviour here: just lots of moping (him), stomping (her), and lamp-eyed soliloquising in front of picture-book landscapes, at least one of which appears to have been clumsily green-screened in after the fact.

The accents are, if anything, even less authentic. This is arguably forgivable with Walken, who plays his part as if he’s in a skit, and delivers an opening narration that plays like a send-up of sub-Waking Ned blarney-fied quirk (“Welcome, welcome to Oireland,” he cheerfully begins. “Moi name’s Tony Reilly. Oi’m dead.”) But the film’s haphazard vowels are less understandable when it comes to Blunt, and completely inexcusable with Dornan, who grew up in Belfast.

Shanley, himself an Irish-American, is capable of romantic, playful scripts that toy with national stereotypes: he wrote the immortal Cher/Nicolas Cage vehicle Moonstruck, set in Brooklyn’s raucous Italian-American enclave. And his 2008 screen version of Doubt, which snagged Oscar nominations for its four main actors, proved he could adapt and direct his own material. But despite a handful of Moonstruck-like moments, including a transporting mid-film trip to the ballet for Blunt, this is deeply embarrassing stuff. And when that final twist lands – well, Dumbstruck is more like it.

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