TORONTO - Margaret Atwood says plans to adapt her novel "Alias Grace" for the big screen are in good hands with actress-turned-director Sarah Polley.

The Booker Prize-winning author says Polley has already completed an outline for the script and is "passionately devoted to the project."

Atwood says the two have had long conversations about the story and that the Oscar-nominated filmmaker has wanted to tackle the Canadian crime tale since she was 18.

"Alias Grace" is inspired by the real-life conviction of a teenage maid accused of killing her employer and his mistress in the 19th Century.

The big-screen plans come as Atwood's non-fiction book, "Payback: Debt and the Shadow Side of Wealth," gets reinvented as a documentary and hits select theatres beginning this weekend.

Although the subject is debt, "Payback" is not a film about money -- it explores the larger idea of what it means to owe something and asks: What happens when the debt is so great it can't be paid back?

Atwood says she never thought her collection of essays would lend itself to the documentary form but says she's impressed with director Jennifer Baichwal's interpretation.

Meanwhile, she says Polley has been pursuing "Alias Grace" for years.

"She did ask if we could hold it for her until she was ready to take it on, so we did," says Atwood.

Polley has proven adept at handling adaptations before.

Her first film, "Away From Her," was based on the Alice Munro short story "The Bear Came Over the Mountain" and earned Polley an Oscar nomination for best adapted screenplay.

"I know her work and I followed her over the years and, as we all know, she is a person of filmmaking integrity," says Atwood.

"I just felt it would be in good hands because the other thing that you want to know is that the person is passionately devoted to the project, which indeed she is, and has been."