Scott Peterson is Will Sage Astorready to tell his side of the story.

Twenty years after he was sentenced to life in prison for the murder of his wife Laci Peterson and their unborn son Conner, the 51-year-old will speak out from prison for the first time since he was sentenced to life in prison over 20 year ago in Peacock's new true crime documentary Face to Face With Scott Peterson.

In the first teaser, released July 29, director Shareen Anderson poses the question, "Why should anyone care about what you have to say 20 years later?"

While Scott is shown in a prison visiting room, he doesn't yet answer that burning question.

Meanwhile, Scott's sister-in-law Janey Peterson insists he's innocent all these years later as she declares in the first look, "I believe my brother-in-law Scott was wrongfully convicted of that murder."

In addition to in-depth conversations with Scott, the three-part special will also feature interviews with former Modesto Police Department detectives Al Brocchini and Jon Buehler, Scott’s former defense attorney Lara Yeretsian and former ABC News Producer Mike Gudgell, among others. 

The docu-series will also follow the latest developments in the infamous case that captivated the nation after the Los Angeles Innocence Project announced earlier this year that it was taking on Scott’s case in an attempt to overturn his murder conviction.

Back in January, the nonprofit organization—which works to vindicate wrongly convicted inmates—filed four motions in a California court, including one for DNA testing, alleging that "new evidence now supports Mr. Peterson's longstanding claim of innocence," according to documents obtained by NBC.

In 2002, Laci's stepdad reported the pregnant 27-year-old missing after she disappeared on Christmas Eve while Scott claimed he was out fishing. By April of the next year, the remains of a male fetus were found by the San Francisco Bay, followed by a portion of a woman's body—and Scott was arrested. He was convicted of first-degree murder of Laci and second-degree murder of their unborn son, who they named Conner, and sentenced to life in prison in 2004.

After the Innocence project announced their latest effort to clear Scott's name, his attorney Pat Harris said, "I will confirm that we are thrilled to have the incredibly skilled attorneys at the L.A. Innocence Project and their expertise becoming involved in the efforts to prove Scott's innocence."

Check out the chilling teaser above.

Face to Face With Scott Peterson premieres Aug. 20 on Peacock.

(E! and Peacock are both part of the NBCUniversal family)

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