True Blood star Stephen Moyer has signed on for director Atom Egoyan's Devil's Knot for Dimension Films.

The drama is based on the wrongfully-convicted West Memphis 3, who were exonerated and released from prison last year after spending nearly two decades in prison for a triple homicide they didn't commit. Stephen Moyer will play John Fogelman, the prosecutor who tried and convicted Damien Wayne Echols, Jessie Miskelly, and Jason Baldwin. He joins a cast that already includes Colin Firth, Reese Witherspoon, Alessandro Nivola, Kristoffer Polaha, Collette Wolfe, Justin Castor, and Kevin Durand.

Atom Egoyan is directing from a screenplay by Scott Derrickson and Paul Harris Boardman, based on the 2003 book Devil's Knot: The True Story Of The West Memphis Three by Mara Leveritt.

Production will begin later this summer in Louisiana. The West Memphis 3's story was also chronicled in a trio of documentaries, Paradise Lost: The Child Murders at Robin Hood Hills, Paradise Lost 2: Revelations, and Paradise Lost 3: Purgatory.