Keira Knightley: How I Choose My Sexy Roles

Keira Knightley is not afraid of intimate on-screen scenes (as is evident in her films Atonement and A Dangerous Method), but she does have a few rules.

"I'm not really interested in the kinds of women who just take off their clothes or have a sex scene and then say something cool," the actress admits in the latest issue of Vogue magazine.

That being said, Knightley was excited to take on the sexually-charged role of Anna Karenina, starring opposite Jude Law. The classic book-turned-movie is about an aristocrat, Anna, and her life-changing affair with the affluent Count Vronsky. 

"She is somebody who breaks her own moral code, and yet the shame and disgust she lives with because of that make her fascinating," Knightley says of her new role.

VIDEO: Keira Knightley Raves About Anna Karenina

Like her character, Knightley admits that she sometimes feels pulled in two directions. The 27-year-old actress recalls, "I literally had no life outside of acting, and I just wanted to go off and not be 'on' all the time, not be photographed. ... I once went to the Glastonbury music festival and was completely surrounded by packs of paparazzi the entire time, so I ended up sitting in a trailer, unable to go out."

For more with Knightley, check out her Vogue spread on newsstands Sept. 25, and on the big screen in Anna Karenina on Nov. 16.