Rooney Mara says it was "necessary" to get a real nipple piercing for her role in "The Girl With The Dragon Tattoo," which, she adds, shows her naked "quite a lot."
Mara, 26, plays hacker and rape survivor Libeth Salander in the film, which is a U.S. film adaptation of the books by Stieg Larsson.
She told Allure magazine in an interview published in its January 2012 issue that it was her choice to get her right nipple pierced for the film, rather than wear a fake jewelry piece, adding that the procedure was "actually not that painful."
"I'm naked quite a lot in the movie," Mara said. "And I thought, (Salander) has it in the book, and she should have it [in the movie]. Because of all the tattoos and the makeup and the piercings, and the physical transformations my body has to go through, it would always feel sort of like I was in costume, even if I was naked. It just felt like a good one to get - a necessary one to get."
"It's not something I want to ever get repierced," she added. "So I'm going to keep it in."
Mara also had her lip, eyebrow and nose pierced, her eyebrows bleached and parts of her head shaved for the role.
"People always ask, 'Were you crying when they cut your hair?'" Mara told Allure. "And it didn't freak me out at all. I was really happy to do it."
The magazine said Mara has since removed her earrings and her eyebrow ring.
The director of the new "Girl With The Dragon Tattoo" film is David Fincher, who also directed Mara in the 2010 movie "The Social Network." He told W magazine earlier this year that her character is a "goth Pippi," referring to popular pig-tailed children's book character Pippi Longstocking.
Salander is also a private investigator and helps Mikael Blomkvist, an investigative journalist played by James Bond actor Daniel Craig, tackle a freelance assignment by an elderly businessman who wants to find out what happened to his grand-niece.
Trent Reznor of Nine Inch Nails and songwriting partner Atticus Ross composed the music for the U.S. version of "The Girl With The Dragon Tattoo" following the success of their soundtrack for "The Social Network. The film also stars "True Blood" actor Alexander Skarsgard's father, Stellan. The movie is rated R for brutal violent content including rape and torture, strong sexuality, graphic nudity and language.
Mara, born Patricia Rooney Mara, is a New York native and the great-granddaughter of New York Giants football team founder Tim Mara and great-granddaughter of Pittsburgh Steelers founder Art Rooney. Her sister Kate stars in the new FX series "American Horror Story."
Mara has also starred in movies such as the remake of "A Nightmare on Elm Street" in 2010 and had a recurring part on the medical drama "ER" in 2009. She is currently filming the movie "Lawless," which stars Ryan Gosling, Christian Bale and Cate Blanchett and is set for release in 2013.
Check out the trailer for "The Girl With The Dragon Tattoo" below as well as information about its characters and the actors playing them.