Keira Knightley is best known for her costume dramas, but she’s totally comfortable going without a costume if the part calls for it. And, often it does. She flaunts her classic beauty topless on the cover of Allure magazine.

“I’m quite rigorous about what gets exposed,” the 27-year-old Brit told the magazine. “No bottom half!”

She couldn’t get more explicit than that. But she’s fair game for anything else. “I don’t mind exposing my t*ts because they’re so small — people really aren’t that interested!” she laughs.

Keira Knightley Exposed in Allure

Keira has appeared topless in half a dozen films in her career, including 2007’s “Atonement,” 2004’s “King Arthur” and 2001’s “The Hole,” when she was just 17-years-old.

“They always pencil in my boobs,” she says of her risque film roles.

“I was only angry when they were really droopy. For ‘King Arthur,’ for a poster, they gave me these really strange droopy tits….I thought, well if you’re going to make me fantasy breasts, at least make perky breasts,” she says.

Because she is so thin, Knightley has touched off speculation she has an eating disorder. Rumors reached a fever pitch in 2008 about the time she was filming “The Edge of Love” and “The Duchess.” It didn’t help that her family had a history of anorexia.

“The anorexic stuff… all of that, it’s always going to have an impact, so I think it did hit pretty hard,” she says. Because you go, oh, maybe that’s right! I knew I wasn’t anorexic, but maybe my body is somehow not right.”

Knightley is starring in another period drama, the upcoming adaptation of Tolstoy’s 1877 novel “Anna Karenina.”

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