Paradise Lost 3: Purgatory already lined up for Toronto premiere.

Acclaimed documentary filmmakers Joe Berlinger and Bruce Sinofsky were in court Friday to witness the ‘West Memphis 3’ being set free in Arkansas. It was already announced that the pair’s latest film about the WM3, Paradise Lost 3: Purgatory, would have its world premiere at the Toronto International Film Festival next month.

They were not allowed to film the hearing but filmed after the hearing at a press conference.

It isn’t known if the filmmakers have time to update the film ahead of the TIFF screening, but it will be re-edited before its January 2012 launch on HBO.

The West Memphis 3 — Jason Baldwin, Damien Echols and Jessie Misskelly — have spent 18 years in prison for wrongful murder convictions — and the filmmakers have been chronicling their struggle for more than 18 years – with films Paradise Lost: The Child Murders at Robin Hood Hills (1996) and Paradise Lost 2: Revelations (2000).

The third film tells the entire story of their struggle, from arrests in 1993 to support for their release (including star supporters such as Johnny Depp, Metallica and Eddie Vedder), to uncovering of new evidence and now with their release. As Echols notes in the new film, if not for the previous documentaries: “…these people would have murdered me, swept this under the rug, and I wouldn’t be anything but a memory right now.”

The case started in May 1993 when the bodies of three young boys were found in West Memphis, Arkansas. The three then-teenagers Baldwin, Echols and Misskelly were arrested a month later.

HBO has backed all three films, and for the third instalment the supervising producer is Nancy Abraham with Sheila Nevins as executive producer. Between its Toronto and HBO premieres, it will also be shown at festivals including New York and The Hamptons.

“Eighteen years and three films ago, we started this journey to document the terrible murders of three innocent boys and the subsequent circus that followed the arrests and convictions of Baldwin, Echols and Misskelly,” said director and producer Joe Berlinger. “To see our work culminate in the righting of this tragic miscarriage of justice is more than a filmmaker could ask for.”

Added co-director Bruce Sinofsky, “Today, we, along with HBO, are humbled to be a part of this remarkable outcome.”

Separately, Atom Egoyan has confirmed that he is planning a feature film inspired by the story of the West Memphis 3.