Saoirse Ronan is to star in The Outrun, an adaptation of Amy Liptrot's best-selling memoir about recovery from addiction.
The four-time Oscar nominee will also produce the film through her new company, Arcade Pictures.
US entertainment trade publication the Hollywood Reporter says The Outrun follows Rona, "a woman fresh out of rehab who, after more than a decade away, returns to Scotland's wild Orkney Islands".
The film will be directed by The Unforgivable director Nora Fingscheidt, who has co-written the screenplay with author Liptrot.
"It was Amy's voice that first drew me to The Outrun," Ronan said in a statement.
"Her unusual way of seeing things in a way that perhaps you only can when you've been to the darkest place you can go within yourself.
"I have been waiting to play a part like this - the messiness, hopefulness, dreaminess, authenticity and humour we want to achieve - I've been scared of it, but with Nora I feel ready."
"There are wonderful gifts already in place to make this a powerful and immersive film," said director Fingscheidt.
"One is the setting, the vast and cinematic landscapes of the Orkney islands; the other is our main actress, Saoirse Ronan, who brings magic to the screen with her unique mix of charisma and emotional depth."
Reacting to Ronan's casting on social media, author Liptrot said: "We're thrilled to have Saoirse Ronan onboard and are looking forward to filming later this year."
The Sandra Bullock-starring The Unforgivable is currently streaming on Netflix.
