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Jessica Alba is ready for "Sin City 2" -- and so is her hair!

The 31-year-old brunette actress began transforming herself back to blond over the weekend to reprise her role as stripper Nancy Callahan in the upcoming sequel to the 2005 hit "Sin City."

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"Bye bye brown hair," she tweeted Thursday with a photo of herself pouting. Documenting her hair color processing, Alba later tweeted a second photo, writing, "Stage 1 -- OK it doesn't look that different but it's a process."

But the next step had a noticeable difference. "Stage 2 of Sin City 2 Nancy hair," she captioned a funny photo of herself on Saturday, showing off her blonder locks with her style team at Robert Ramos of Estilo Salon in Los Angeles posing in the background.

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The process was finally completed later that day. "She got roots that Nancy. Sin City 2," Alba wrote. The actress' new ombre 'do is blond on the bottom and brown on top.

On Sunday, with her new hair all done, Alba went to a gun range to practice shooting. She tweeted, "What a way to start the day -- training for a movie is sorta fun."

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Directors Frank Miller and Robert Rodriquez are teaming up again for the sexy, graphic-novel-inspired "Sin City: A Dame to Kill," which has a release date set for Oct. 4, 2013.


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