About a century and a half ago, a boatload of impoverished Welsh folk left the hills and valleys behind for a new life in the untamed wilderness of - where else - Argentina.
Regrettably, while director Marc Evans uses this intriguing geo-historical link as a starting point for his twin journeys of discovery, he leaves it largely unexplored.
Instead, he subjects us to a double dose of protracted navel-gazing in Welsh and Spanish, one of which ends with yawnsome predictability and the other with an improbable (and certainly illegal) Viking funeral.
In Cardiff, Gwen (Nia Roberts) and her photographer boyfriend Rhys (Matthew Gravelle) are struggling with infertility. So his upcoming assignment in rural Argentina presents a great opportunity for them to leave their worries behind.
Unfortunately the seeds of doubt germinate in both their minds as soon as their rugged, Welsh-Patagonian guide (Matthew Rhys) appears.
Meanwhile, old Cerys (Marta Lubos) has dragged her young neighbour Alejandro (Nahaul Perez Biscayart) on a wild-ish goose chase to Wales to find the farm on which her mother was raised.
Aside from a pair of joy-riding hoodies, the entire population of Wales bends over backwards to help the odd couple on their way - even singing sensation Duffy (in the guise of a good-time country girl). So far, so yaki da.
The unconnected stories allow Evans to dwell on past and future, and dwell is what he does.
Unobtrusively performed but increasingly indulgent and full of clunky similes (a dead dog on the road; a Falklands war veteran unable to let go), the only surprise in Patagonia is how quickly it depletes its reserves of goodwill.
Still, Duffy fans will be cheered that their girl seems as at home in front of the camera as she does on stage. Thank heaven for small Mercys.
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