Transcript for Star-Studded Cast Takes on the New Movie 'Wild'
And lots of people are talking about Reese Witherspoon's latest movie, "Wild." It's based on a true story of a woman who went on an epic 1,000-mile trek to find herself. Cameron Mathison sat down with the stars. I have another 300 miles to walk. Reporter: It's the performance generating buzz. Cheryl sent me her manuscript. I read it in 24 hours. I called her immediately. I said this is what I have been looking for. Reporter: She plays Cheryl trade, the character at the center of "Wild" a story of her journey on the pacific trail. It helped her recover. The way she writes is so honest. Sometimes unflinchingly truthful. She has a thing with honesty. Reese is like, did you really have to write that? How did you know she had the character in her? I didn't have to push her on guide her. She had it inside of herring even though she was scared. Reporter: In the film, she carries the same 70-pound backpack that Cheryl lugged when she hiked the trail. How heavy was it? I have to ask? It was heavy. She did it by here's. Alone, completely alone. I would be so scared. What is it like hearing these three talk about your life? It's such an honor. Every once in awhile, I'll stop and think about where it began and how far I have traveled. I moved into my life. I became the person my mother raised me to be. Reporter: The film tells the story through flashbacks about Cheryl's relationship with her mother, bob bi. If there's one thing I can teach you, it's about finding your best self. When you do, hang on to it. I hand T read anything with this level of honesty and depth of love. And had not seen it in a movie. Reporter: Witherspoon was drawn to the material because it tells the story of a complicated and not always likable woman. You can put yourself in the way of beauty. Reporter: Did you ever thing, all of this? I never imagined. It's everything I intended. Reporter: A couple of things you did learn? Life lessons how you cope with loss. And there's so much inside of you. Love can pro tell you forward in life. You're going to make it. You're going to be okay. Reporter: For "Good morning America," Cameron math son, ABC news, Hollywood.
This transcript has been automatically generated and may not be 100% accurate.