There's a small piece on "Haywire" that says Gina Carano's voice was digitally altered by Soderburgh, who wanted it deeper for the part, and as a way to differentiate her from "Gina Carano, the fighter."
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Gotta say, from what I've seen in the trailer and in pictures where she's done up, I hope she gets more into the acting side of things and stops getting punched in the face. Because, to borrow from North By Northwest, "It's a nice face."
Can a woman be a major action-film star?