Almost a decade later, Alba, 33, is back in the sequel and told E! News how she has changed in that time.
"I feel really comfortable, I feel really grounded, I feel like a woman," she said. "I felt like a girl [before, during the first movie]. I was just on this wild ride of the business and I didn't feel like I was in control of my destiny or where I was going to end up or my path."
She continued, "Now, I feel very much in control. I feel great. I've been doing this for 20 years. I have a very different idea of my place and where i want to be."
Alba talked about her "new-found kind of confidence" and said it comes from "having a personal life ... I have something that so important to me: my family, obviously. I have friendships that I can't live without as well."
As for Alba's sexy Maxim shoot for this month's cover, she said, "I just have an ownership of my body and of myself as a woman that I didn't really have before," adding how things are different promoting this movie now through photo shoots and interviews.
"I was such a tomboy, and I would always kind of like try and do role-playing to try and do these sexy things, but now I'm very much a woman," she added. "I know who I am, I'm confident in my sexuality and now it's not so much of a departure from myself when I have to do photo shoots or play a character."
"Sin City 2: A Dame to Kill For" hits theaters later this month.