No one is more efficient or merciless about punishing us than ourselves. The older I get, the more regrets I accumulate, and there comes a point where you can either let yourself get crushed by the weight of them, or you can figure out a way to forgive yourself and let things go.

"Wild," the latest film from director Jean-Marc Vallee, is not what I expected. I knew it was about a woman hiking the Pacific Crest Trail. That's 2,663 miles, from the US border at Mexico to the US border at Canada. I didn't know why she was hiking or what kind of drama the film would try to wring from the trip, and honestly, the concept didn't hook me in a way that made the film a priority. What I saw, though, was something tough and honest and unsentimental, and it's a pretty major piece of work for star Reese Witherspoon.

Nick Hornby's adaptation of Cheryl Strayed's autobiographical book is structured beautifully, only gradually pulling back the curtain on all of the damage that has led Cheryl to hit the PCT. This is not a hike for her; it's a scourging, a penance. What she's doing penance for is the heart of the film, and instead of front-loading all of that information, Hornby tries to give it to us in a way that feels more natural, more like the organic shape of memory, where things bubble up and connections are made between things and you sometimes have no real control over what comes to the surface. Little by little, Cheryl finds herself pounded by these things she's tried to keep pushed down and bottled up, and eventually, she has no choice but to deal with them because there's nowhere for her to hide.

Witherspoon does really uncompromising work here, playing Cheryl without any hesitancy or any fear or any ego. It's not a glamorous role, and she doesn't try to make Cheryl seem perfect, and she doesn't sand off this woman's rough edges. One of the major threads of memory that come unraveled during the film has to do with Cheryl's relationship to her mother Bobbi (Laura Dern), and she is frequently horrible to her mother. There's a contempt that she has for her that is both very real and very ugly. There's a moment in the car as they're driving somewhere when Cheryl observes, positively chipper about it, "It must be strange that I'm so much more sophisticated than you," and watching the full impact of that play across Dern's face as she struggles to figure out how to respond gutted me. Bobbi isn't terribly sophisticated, but that's because she's sacrificed so much to raise her kids, and there is an unflappable kindness and optimism to Bobbi that is very moving.

As the film jumps from the present day story of Cheryl on her hike into the past as we see what brought her to this point, it doesn't really hew to what is considered typical Hollywood structure. The film isn't about giant epiphanies and phony healing; instead, it's about the small ways we put ourselves back together and the million tiny ways that life is always trying to pull us apart. Cheryl's terrible choices come from genuine pain, but the film doesn't excuse them just like it doesn't condemn her. It's a very hard line to walk, and the fact that the film is able to present all of this without judgment is one of the most impressive things about it.

It's beautifully made, and I think my favorite thing about the photography by Yves Belanger is that it's not just about making nature look pretty. What I think Vallee does well as a filmmaker in both this and "Dallas Buyers Club" is take us into his protagonists so we feel what they feel. I think Ron Woodruff is a hard guy to like in "Dallas Buyers Club," but he's incredibly easy to empathize with because of the way Vallee makes the film feel like we're experiencing it from Ron's point-of-view. The same thing is true here. Vallee is adept at making the mechanics of his films invisible. They are far more emotional experiences than intellectual ones. Vallee seems happy leaving us to figure out our own responses to who these people are, instead simply trying to make us feel what they feel.

"Wild" is strong adult filmmaking, and I'm glad Witherspoon decided to star in this instead of "Gone Girl," which she also produced. We've seen the type-A personality from her before, wound too tight and starting to crack, and while she does it well, this is a very different performance for her, stripped down and human and raw. While the supporting cast all does good work, this is her show. She's frequently onscreen alone, and she's the one who has to convince us that all of these things that we're seeing are going on inside this woman, that she is driven to make this hike, and when it does finally transform her, it's Witherspoon who has to open wide and lay this woman's soul bare for us. "Wild" is one of the most quietly rewarding of the big films opening at the end of the year, and well worth a trip to the theater.

"Wild" is in theaters now.

A respected critic and commentator for fifteen years, Drew McWeeny helped create the online film community as "Moriarty" at Ain't It Cool News, and now proudly leads two budding Film Nerds in their ongoing movie education.