Reese Witherspoon on "incredibly moving" story behind "Wild"

Reese Witherspoon sets out on a path to self-discovery in the new movie, "Wild".

The Oscar winner stars as Cheryl Strayed, who embarked on the 1,100-mile journey after abusing drugs, suffering through a failed marriage and losing her mother.

"I called my agent and I said I have to talk to this woman," Witherspoon told CBS News. "I told her how incredibly moving I found her book and that it was definitely one of the most important books I read in my life."

Strayed says Witherspoon -- who was also a producer on the film -- was one of her earliest supporters.

"Reese read it before it came out and I took notes and the first thing she said was, 'get ready, this book is going to be a best-seller'," Strayed said. "She was right!"

Laura Dern co-stars as Cheryl's beloved mother Bobbi.

"All these incredible words of wisdom she gave you are now ours; we get to be mothered by Bobbi as well," Dern said.

"Wild" is directed by Jean-Marc Valle, whose last film, "Dallas Buyers Club", earned Oscars for its two leads. Many expect this role will bring Witherspoon her second best actress nomination.

Witherspoon won a best actress Oscar for the film "Walk the Line."

"Wild" opens in theaters in limited release on Friday.