Maggie Gyllenhaal has signed on to star in a biopic on musician Bill Monroe.

The 'Nanny McPhee Returns' actress will star alongside her husband Peter Sarsgaard in the project, directed by Finn Taylor.

She told Screen Crave: "Bill Monroe, who invented bluegrass music had a kind of Sid and Nancy-style affair with this woman Bessie Lee Maudin throughout his life and T-Bone Burnett's going to do the music and Callie Khouri - who wrote 'Thelma & Louise' - wrote The Script so we're going to do that together."

Following an Oscar-nomination for her role in 2009's 'Crazy Heart', Maggie's career has been relatively quiet, although she can next been seen in Tanya Wexler's romantic comedy 'Hysteria' alongside Hugh Dancy and Rupert Everett.

The Bill Monroe picture will not be the first time she has worked with her husband Peter - with whom she has three-year-old daughter Ramona; the previously worked on stage show 'Uncle Vanya' in 2009.