'Captive' tells how Rick Warren's 'The Purpose Driven Life' changed lives of drug addict and her captor

'Captive' is based on the novel written by Ashley Smith entitled 'Unlikely Angel: The Untold Story of the Atlanta Hostage Hero.'(Paramount Pictures)

The new faith-based film called "Captive," which stars David Oyelowo and Kate Mara, tells the true-to-life story of meth addict Ashley Robinson (formerly Ashley Smith) who was held captive by Brian Nichols, and how both their lives were changed because of Pastor Rick Warren's bestselling book "The Purpose Driven Life."

The film, which will be released on Sept. 18, 2015, is directed by Jerry Jameson with the screenplay written by Brian Bird. It is based on the novel written by Smith herself entitled "Unlikely Angel: The Untold Story of the Atlanta Hostage Hero."

Mara plays meth addict Smith, who was held captive in her own apartment for seven hours back in March 2005 by Nichols, played by Oyelowo. Nichols was trying to evade authorities after bolting out of jail and murdering the judge assigned to his case.

While cooped up in her apartment, Smith begins reading aloud chapter 32 of Warren's book "The Purpose Driven Life" in hopes of encouraging her captor to let her go.

Warren's book not only softens Nichols' heart but touches Smith's own in such a profound way that she never dealt with drugs again after that night.

"In the months since being held hostage by Nichols, a great deal in my life has changed. Some days I wake up and think everything has changed. My life is by no means perfect, but it is different. In many ways—the most important ways—it finally seems to be on the right track; and for that I am grateful," Smith writes in her book.

Before Nichols took her hostage, Smith described herself as a struggling mother dealing with drug addiction, trying to regain custody of her daughter, and just simply trying to get her life in order. She was not prepared for publicity when it came, but God pulled her out of it in the end as a brand-new person with a renewed purpose in life.