Sporadically fascinating but ultimately forgettable, 'Meek's Cutoff' is the most poorly played game of Oregon Trail I've ever seen, except director Kelly Reichardt ('Wendy and Lucy') is more interested in afflicting her settlers with paranoid tedium than with cholera. The year is 1845 and three married couples (intermittent offspring included) are trekking across the Oregon desert with their hooded wagons in search of, well, anything else. Water would be nice, and if they happen to stumble across some gold along the way, they'll take that, too. The party is lead by a paid frontiersman named Stephen Meek (Bruce Greenwood, unrecognizable beneath the scruffy muck of the era), a suspicious and confidently virile sort whose stubborn but potentially false directions might prove fatal in such dire circumstances. Tensions run high as resources run low, but when the group captures a lone Native American (Rod Rondeaux) and forces him to lead them to whatever oasis supplies his community, the question of water is superseded by fears of an ambush.

A detailed period piece like 'Meek's Cutoff' initially appears to be something of a departure for Reichardt, a minimalist filmmaker whose brief and bare portraits of American lives seem found rather than filmed. 'River of Grass' was a slacker masterpiece, 'Old Joy' was a widely acclaimed whisper between two friends camping in the woods of Oregon, and 'Wendy and Lucy' was a gently devastating tale of a girl and her dog. But don't be fooled by the baked and expansive backdrop of her latest film or its believably harried scenes of musket cleaning, for better or worse this is vintage Reichardt. Introspection, unmannered conversations, and swallowed emotions are the name of the game, and a series of deceptively mundane moments seem to cohere into a rather pointed narrative when no one's looking.

'Meek's Cutoff' considers the endlessly enigmatic desert with far more detail than it does most of its characters, and Reichardt effortlessly channels her inner David Lean, immaculately framing the unkind terrain despite the fact that the camera in her previous films kept up with its subjects like a shaggy pet. A square-ish and confining 4:3 aspect ratio not only affords the film an intimacy unusual for a Western, but provides the filmmaker with a crutch of sorts in addition to boxing her characters in a prison of scorched earth. If '(500) Days of Summer' can get Marc Webb hired to direct the new Spider-man, 'Meek's Cutoff' is enough of a visual spectacle to put Reichardt on the shortlist for, uh, at least a 'Captain Planet' blockbuster or something.

So it's to my great and bummed surprise that for all of her newfound visual aplomb, Reichardt fumbles with her cadre of characters. 'Meek's Cutoff is a film attuned to how the correlation between ignorance and self-destruction has shaped American history, and the small wagon train at the heart of this parable is naturally populated like the cast of survival horror film (a bunch of critics have alluded to Hitchcock's 'Lifeboat'), and when the Cayuse shows up it's easy to imagine them getting picked off one by one. Zoe Kazan and Paul Dano are the young, impetuous, and distractingly hip couple who - if this were a Wes Craven film - would be unhelpfully screaming at the terrors beyond the frame.

The milieu naturally channels Dano's unforgettably violent and affected performance in 'There Will Be Blood,' and he's believable as a kid desperately trying to pretend that he's not too young for the deadly frontier. Kazan doesn't fare quite so well as the group's relentlessly fearful screecher. She's saddled with a catastrophically thankless one-note role, and her insistence that the Cayuse is leading them into a trap proves wearisome where the rest of the ensemble is merely weary. Shirley Henderson and Neal Huff acquit themselves a little better as a God-fearing and believably old-timey duo, but 'Meek's Cutoff' is easily at its best when focusing on Michelle Williams' Emily, the haphazardly stoic newlywed around whom the rest of the more archetypical troupe orbits.

'Meek's Cutoff' is dominated by a pedantically political argument between those who distrust the Cayuse and those whose reason is a bit less clouded by prejudice, but it's only through Williams' predictably sublime performance that the simple partisan parable is graced with a deeper human touch. We never learn much about her (or anyone else, for that matter), but Williams' Emily is completely alive with the wariness of her times, and as a result she's the only character you're ever given reason to care about (Jonathan Raymond's script seems to hamper the other characters at Emily's expense).

More than just a mere proxy for the audience, she's also a hugely believable genre hero, forthright without being foolhardy and not afraid to aim a musket taller than she is at anyone who threatens her survival. It's a riveting performance, and one made all the more interesting by the fact that Emily - like the rest of the women - has no real say in the direction of the caravan or the fate of the Cayuse (a dynamic that makes her as relatably powerless as an audience that might want to yell verdicts at the screen). The group is a bit too evenly divided for the adventure to feel like '12 Angry Men' on the range, but Emily (and her sweet husband played by Will Patton) are level heads in an era when people manifested destiny with guns blazing and an implicit disdain for the bevy of indigenous cultures they didn't care to understand.

It's a timeless (and true) story of people having to make critical decisions on the basis of incomplete information, but a conflict better suited to an episode of 'The Twilight Zone' than a feature film, which at 104 minutes is needlessly overlong for a filmmaker whose most effective works have been a whole reel shorter. Reichardt's attention to period detail and affinity for period ennui is absorbing until it's not, and for every moment of palpable menace there's a moment that feels like it's as much of a slog for the film's audience as it is for its characters. It's the enigmatic bits that really sing, especially a note-perfect final shot that so fluently "accepts the mystery" that you wish it were capping a better film. As it stands, 'Meek's Cutoff' is what happens when a skilled director is challenged to a stalemate by a particularly frustrating script, and confronts it in the only way she knows how. It might be the biggest film of Reichardt's career, but she's never told a story that feels so small.