“The Last Sin Eater” comes to us from FoxFaith, a label from Fox Faithless (as perhaps we should now call it) designed to market a new product line to Christian moviegoers who have been underserved (when not actually insulted) by Hollywood’s mainstream studios.

I’m afraid this demographic may not feel that it is much better off if “The Last Sin Eater” is the kind of movie they can expect from Fox-Faith.

Had I been advising Michael Landon Jr., who directed, or Brian Bird, who joined him in adapting Francine Rivers’s novel, I would have told them to go all out for the fairy tale. As it is, they mix their fairy tale with a realistic narrative, and the two step all over each other’s toes before crashing down in a tangled heap together.

Part of the problem is that, on the one hand, the film is weirdly specific about the time and place of its setting — which is Appalachia in 1850 — and on the other, it is quite obviously set in never-never land.

Not only does the landscape not look like Appalachia — the movie was shot in Utah — but the people don’t look or talk like people from Appalachia. Supposedly a community of Welsh farmers who settled in this “cove” — surely this is an interloping term from the littoral and not native to the Appalachian “hollers” — a generation ago, they seem never to have encountered any Americans, except a few Indians, on the way.

Moreover, these alleged Welshmen and women have Scottish, Irish, or Dutch surnames and speak an otherworldly brogue that is not consistent but which has traces of Irish and Scottish in it and little Welsh.

Most curiously, so far from being chapelgoers like the actual Welsh, none of them appears ever to have heard of Christianity or of Jesus Christ except as an expletive. Instead, they practice a weird religion of their own that is said to have come down to them from their Welsh ancestors.

The community chooses by lot a “Sin Eater” from among its members. Thereafter, the Sin Eater is required to live apart from everybody else in a cave on Dead Man’s Mountain and to wear a spooky-looking black cloak and hood. He must never be seen by anyone in the community again.

When someone dies, a relative rings the passing bell and the neighbors gather at night by the graveside. Having laid a shroud over the body, they put some bread and a skin of wine on it, then all turn their backs as the Sin Eater arrives, eats the bread and drinks the wine, and pronounces a sort of absolution over the corpse.

One day an 11-year-old girl, Cadi Forbes (Liana Liberato), who is eaten up with guilt for (as she thinks) killing her little sister, goes in search of the Sin Eater. “I can’t live my whole life with what I have done,” she tells Miz Elda (Louise Fletcher — once Nurse Ratched but now the sweetest little old lady you’d ever want to meet). Accompanied by a neighbor boy (Soren Fulton) and a clearly angelic imaginary friend called Lilybet (Thea Rose), Cadi sets out in search of the Sin Eater to force him to eat her sins before she dies — a thing which has never been thought of heretofore.

Left at that, the movie might have done well enough as a sort of parable, set in a parallel universe, where the eternal drama of sin and redemption is repeated with different dramatis personae from those we are familiar with. Instead, it veers into mistaken literalism as Cadi’s quest brings to light the dark secrets surrounding the appointment of the Sin Eater and the guilty memory of the atrocity that the community has been living with but hiding from for 20 years.

Such a realistic drama superimposed on the fairy tale only has the effect of making everything look hopelessly unreal. On top of that, a “Man of God” (Henry Thomas) appears among them to teach them that “the original Sin Eater” did his job 19 centuries before, a bit of information which, along with the bible that he leaves with them, turns all the little “cove” of heathen Welsh into good Baptists, with the old Sin Eater — now, by the way, reunited with the lady-love who has waited for him through all the sin-eating years — as the new Pastor.

I don’t know whether this ending will satisfy and uplift the Christian audience FoxFaith is catering to, but I can’t see it doing much business beyond it.

jbowman@nysun.com