Wild Reese Witherspoon, Laura Dern, Thomas Sadoski. Directed by Jean-Marc Vallée. Rated R. Opens Friday.

Cheryl Strayed’s 2012 memoir Wild is the kind of book Hollywood could easily turn into a trite inspirational story, with blatant awards-baiting for a movie star looking to be taken seriously. But producer/star Reese Witherspoon (who optioned the movie rights before the book was even published) and director Jean-Marc Vallée (Dallas Buyers Club) clearly have great respect for Strayed and the story of her attempt to leave behind a troubled past while hiking more than a thousand miles along the Pacific Crest Trail from California to Oregon. They approach the story with grace and subtlety, downplaying big revelations and instead focusing on the small steps that Cheryl (Witherspoon) took, both on the trail and in coming to terms with her inner turmoil.

The film slips back and forth between present and past thanks to masterful editing, as the inexperienced Cheryl embarks on this massive undertaking while haunted by the death of her mother (Laura Dern) from cancer, her divorce from her well-intentioned husband (The Newsroom’s Thomas Sadoski) and her struggles with drug addiction and risky sex. The flashbacks intertwine beautifully with the present-day scenes, and Witherspoon’s performance is full of vulnerability and regret. Cheryl has made bad choices and hurt the people she loves, but the movie neither pities nor celebrates her. She’s a flawed human being working to forgive herself and move forward, through an endeavor both foolish and intensely cathartic. And just when her reflections and reinventions seem in danger of becoming repetitive, the movie ends, leaving Cheryl and its audience in a place of satisfying uncertainty.