Flicka,Seabiscuit,Black Beauty,National Velvet: cinema is not short on stories about the sacred bond between humans and their equine spirit animals.

But ifLean On Peteis a horse movie, its a Trojan one: a raw-boned, melancholic mood piece that trades in none of the easy inspiration its soft-glow poster and trailer might suggest.

Charlie Plummer stars as Charley, a kid scraping by in the Pacific Northwest with his single dad, Ray (Vikings Travis Fimmel).

Lean on Pete

Credit: Scott Patrick Green/A24

Ray isnt a bad guy, but hes barely a parent; while he scrounges for beer money and amiably works his way through a long string of strippers and secretaries, his 15-year-old son is mostly left to raise himself.

Thats how Charley ends up wandering over one day to a nearby paddock, where he offers up his services to Del (Steve Buscemi), a race-circuit journeyman and inveterate crank he spits out his words like hes being paid by the epithet in a David Mamet play with a stable that needs caring for.

Through Del and his longtime jockey Bonnie (Chloe Sevigny), Charley carves out some temporary sense of place and family, and earns enough petty cash to bolster his habitual dinners of tap water and Capn Crunch.

He also falls in love with Lean On Pete, a glossy-brown quarterhorse with soft black eyes and a career clock thats quickly winding down.

Plummer, probably best known as the troubled teenage Getty scion in last yearsAll the Money in the World, appears in every scene here and whether through good luck or great instinct, writer-director Andrew Haigh has found exactly the right muse to hang the delicate frame of his story on, coaxing out a performance so interior and naturalistic it hardly feels like acting at all.

As in his two previous movies,45 YearsandWeekend, Haigh is much less interested in conventional character building and plot machinations than in the quiet accumulation of small moments.

And his script, based on a 2010 novel by Willy Vlautin, unfurls with a sort of lyrical, off-kilter grace, imbuing his rest stops and racetracks and wide-open Western landscapes with an aura so authentically out of time that its a mild shock near the end to see someone suddenly pull out an iPhone.

As Charleys situation becomes increasingly precarious, the movie also becomes a meditation not just on what it is to live on the social and economic fringes in America, but how easy it is to slip through the cracks entirely.

That may feel like a bait and switch to viewers who just came for some nice boy-and-his-horse uplift, butPeteis no kind of fairytale; instead, its something far sadder and better and more real.A-