Reese Witherspoon will star in Devil's Knot, Atom Egoyan's movie about the West Memphis Three, one of the film's producers told TheWrap on Thursday.

The Weinstein Co.'s Dimension Films has been developing the Devil's Knot project for years. The West Memphis Three were also the subjects of a three-part HBO documentary, Paradise Lost.

In the new film, Witherspoon will play Pam Hobbs, the mother of three 8-year-old boys who were brutally murdered in West Memphis, Ark., in May 1993.

Hobbs had been among those who accused Damien Echols, Jessie Misskelley and Jason Baldwin of committing the infamous murders. In November 2007, she said new evidence had changed her mind.

Did I really believe it, no, not 100 percent that they did it, she told Jonesboro, Ark.-based KAIT-TV. I didn't believe they were capable enough or smart enough to have committed the crime, cleaned the scene up and be guilty for it.

After spending 17 years in prison, Echols, Misskelley and Baldwin were released from prison in August as part of a plea deal.

Over the years, Eddie Vedder, Henry Rollins and other prominent musicians had raised money in support of the West Memphis Three, who had maintained their innocence all along.

Dimension acquired the rights to journalist Mara Leveritt's book Devil's Knot: The True Story of the West Memphis Three in 2006, and hired Scott Derrickson and Paul Harris Boardman to write the script.

Richard Saperstein, Elizabeth Fowler, Boardman and Clark Peterson will produce Dimension's movie.