When you see Jessica Alba performing as exotic dancer Nancy the upcoming Sin City: A Dame to Kill For later this year, be appreciative: Apparently, those dance moves were really hard to learn. 

"I had to learn a bunch of dance sequences for it," Alba told Vulture of the upcoming film during a Sundance party for her new comedy A.C.O.D. "I do a lot more dancing in this one." Always good news. In fact, let us take a moment to remember her first scene as Nancy from 2005's Sin City

Moving on: "It was kind of crazy," Alba continued. "It was very, very difficult, and you’ll see why." If you needed more of a reason to see this film other than the excellent cast, you should have one now. Sin City: A Dame to Kill For will be released in theaters on October 2, 2013.

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[via Vulture]