TORONTO - Colin Firth admits he knew nothing about the West Memphis Three when he first encountered "Devil's Knot," a dramatic take on the mysterious slayings of three Arkansas boys in 1993 and the controversial conviction of three teens in their deaths.

But he says he was immediately fascinated by the "diabolical" misconduct of justice involved, and was tantalized by the unusual vision of Canadian director Atom Egoyan.

The Oscar-winning British actor says this is not a story that easily fits Hollywood's storytelling mould, and that's what made Egoyan especially suited to putting the infamous tale on the big screen.

Questions linger to this day about what really happened, and Firth notes that Egoyan wasn't afraid to leave those loose ends dangling in the movie.

"He finds things that other people might not notice and if this is a case that can't be solved easily then that's what's interesting — let's be honest about that, let's not try and manufacture resolutions which aren't really there, let's see what our relationship is with the insoluble, with frustration," Firth said during a stop at the Toronto International Film Festival back in September.

"He's, I think, a real master of tone and of the mood of an experience. (This is) a story which has so many threads and so many strands, and it's not one single arc and there isn't a single protagonist. To me, he's integrated the film through that pervading mood. It's the way he lights things, and the way he uses music, and the way he creates connections and in ways that aren't conventional."

That includes surreal dream sequences, a recreation of the forest in which the boys disappeared and a stunning shot in which searchers come across three small bodies, hog-tied and naked.

Egoyan says it was important to include that especially disturbing image, insisting it further speaks to the almost supernatural atmosphere that surrounded the disappearance of three eight-year-olds from a small Arkansas town.

"That again is one of the most identifying aspects of this case ... how spooky it is to see the state of the bodies, to see that they were stripped bare, that the knots were meticulously sort of tied and yet there's no hard evidence of any disturbance around," Egoyan said during the festival.

"There was no blood, there were no footprints, there was no disturbance in the bush, it just seems like this thing was dropped into this swamp. You couldn't have written it as a drama because no one would believe it and yet we know it actually happened."

One month after the murders, detectives revealed a theory for the grotesque crime — that the children had been killed by members of a satanic cult. What's more, they named three teenage suspects, and despite having no physical evidence, prosecutors succeeded in securing guilty verdicts for all.

It would take well over a decade for questionable evidence to be re-examined once more. While anticipating a new trial, Damien Echols, Jessie Misskelley Jr., and Jason Baldwin negotiated a rare plea that allowed them to maintain their innocence and be set free in August 2011.

Firth plays real-life Arkansas investigator Ron Lax, whose persistent investigation is credited with helping lead to the trio's eventual release after 18 years in prison, although the film focuses on the initial conviction.

Reese Witherspoon plays devastated mother Pam Hobbs, who, in the film, harbours growing doubts about the prosecution's case as troubling details about her son's death emerge.

The sprawling broader cast includes Mireille Enos of "The Killing," Stephen Moyer of "True Blood" and Elias Koteas of "Exotica."

"Devil's Knot" reunites Firth with Egoyan after the two paired for the 2005 mystery "Where the Truth Lies." Egoyan says the acclaimed Brit was perfect for the role of Lax.

"There's no one else I could have imagined playing this role because he's someone who's able to have this critical intelligence and yet is so empathetic at all times," Egoyan said of Firth, who won an Oscar for playing a stuttering King George VI of Britain in the 2010 crowd-pleaser "The King's Speech."

"He's magnificent and as an outsider into this culture he just sort of seemed to embody that. It was a great pleasure to work with him. I still think that the performance he did in 'Where the Truth Lies' is like criminally unrepresented, it was so risky for him at that point to do that movie. I love him."

Meanwhile, Firth says he joined the project — an adaptation by Scott Derrickson and Paul Harris Boardman of Mara Leveritt's true crime book, "Devil's Knot: The True Story of the West Memphis Three" — in large part because of his admiration for "The Sweet Hereafter" director.

"He's not a slave to his roots but he's maintained them enough to keep loyalties going and he works very, very much on his own terms," said Firth.

"And I think after all these years there's a great deal to be said for that."

"Devil's Knot" opens Friday in Toronto and Vancouver.

News from © The Canadian Press, 2014