Anyone who found Kelly Reichardt’s last film, the widely-praised “Old Joy,” a tedious, talky slog through some good-looking Northwest territory will be pleased to learn that this new film is better, though it still meanders in a minimalist fashion that can grow wearisome. The reason is that “Wendy and Lucy” has a story of sorts, if a very slight one, and more than two characters, some of whom are engaging and likable. It also showcases a performance by Michelle Williams that’s impressive in its control and honesty.

It does not, however, have the poetic spirit that the minimalist exercises of Gus Van Sant, for example, so beautifully express. Instead the picture opts for a gritty, matter-of-fact approach that mimics documentaries. That wouldn’t be a problem if it exhibited a considered sense of shape and molding. But it doesn’t. A good many scenes feel like improvisations, whether they are or not, and many tend to drag; even the opening shot of Wendy ambling through the forest with her dog Lucy seems to go on and on, however pretty the luminous sunlight coming through the branches might be.

Still, Williams is remarkable as Wendy, a sad-faced drifter driving to Alaska in search of work. Her companion is her golden retriever Lucy, a gregarious hound that brings out her only smiles and on which she lavishes affection. When her car breaks down in a small Oregon town and she finds herself broke, she tries to steal some dog food from a grocery and is arrested for shoplifting. When after being released she returns to the spot where she’d tied Lucy up, the dog’s gone. The rest of the picture follows Wendy as she tries desperately to find her dog and get her car fixed.

A good deal of footage is devoted to Wendy’s wanderings, first with Lucy in tow and then in search for her. Along the way she bumps into a few folk, some nicer than others. On the one hand there are the overly scrupulous grocery clerk (John Robinson) who insists that she be arrested and the menacing fellow (Larry Fessenden) who threatens her as she sleeps in a park. On the other, Will Patton offers a nice cameo as the garage mechanic she consults about getting her car back running, and Walter Dalton is genuinely touching as a security guard who shows the girl some much-needed kindness in small but important ways.

But as good as all of them are, it’s Williams—along with the dog—who holds “Wendy and Lucy” together with a performance that captures her character’s fragile stoicism and underlying vulnerability without a false note. Reichardt’s bare-bones style, as desultory as it is at many points, helps her maintain the feeling of authenticity, and Sam Levy’s stripped-down cinematography does as well. The result is a turn that’s comparable to the breakthrough one that Ashley Judd gave as another woman living on the margins of society in Victor Nunez’s 1993 gem, “Ruby in Paradise.”

But while “Wendy and Lucy” paints a frequently affecting snapshot of a rudderless young woman in difficult straits, its homespun approach never achieves the transcendent effect that Nunez’s picture, or the best of Van Sant’s minimalist films, have.

Nevertheless you’re unlikely to shake the simple sight of Williams’ face registering something close to despair as she finds out what happened to Lucy and must decide how best to move on.