Rooney Mara walking to the set of her new movie 'The Bitter Pill' in New York City. Credit: Splash News Online

New film, new hair!

In NYC Tuesday, Rooney Mara's signature pitch-black, shoulder length hair and full, blunt bangs were absent on the set of her upcoming film, The Bitter Pill.

Rocking a long, ombre wig, the Girl with the Dragon Tattoo actress channeled her all-American looking character in The Social Network, where Mara played the role of Mark Zuckerberg's (Jesse Eisenberg) scorned girlfriend Erica in the Facebook flick.

In The Bitter Pill, the 26-year-old star plays Emily Hawkins, a woman who depends on prescription meds as she awaits her husband's release from prison.

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The flick is due to hit theaters in 2013 and also stars Channing Tatum, Jude Law and Catherine Zeta-Jones.