Actress Keira Knightley said she is straying away from period dramas after discovering a new "chapter" in her life.

The 29-year-old is set to make her singing debut in feelgood film Begin Again, out next month, stars opposite singer Adam Levine, who found fame with American rock band Maroon 5.

Knightley, who played the tragic heroine in 2005's Pride & Prejudice and more recently took the title role in 2012's Anna Karenina, said she was drawn to the scripts because "you can f*** with people's notion of the past."

She added: "But the bitch is the time spent getting ready. It was the practicality of life that made me think, after Anna Karenina, how this would be nicer if I got two hours more sleep a day.

"Begin Again came at a point when I was questioning what I put out into the world, and I was putting out a lot of dark films. This film is an innocent view of the music industry, not involving sex, drugs or rock 'n' roll, so some tribes of music fan will loathe it. But I was looking for something about hope, and that's certainly what this is."