Alba's dance prep for Sin City 2
Jessica Alba did plenty of dance preparation to get in shape for returning to her stripper role in Sin City: A Dame To Kill For.
Choreographer Jennifer 'JJ Dancer' Johnson told People how worked together with Jessica on her moves as Nancy Callahan, the stripper she first played in 2005's Sin City.
JJ explained: "We just started to move to the music, and we were getting her used to the sensuality and moving around in heels in the beginning. Then we started choreographing routines on her body. She would bring songs, I would bring songs - some were rock, some were sad, some were edgy, but they were all sexy."
The dance classes would last between two and five hours, and Jennifer continued: "She would just follow my body. I'd have her winding, grinding and moving. We would grab the wall, I'd have her crawling, arching, humping. It got real up in there.
"She just got the heels - she would wear clothes that showed her body and made her feel sexy. We went there!"
The dance instructor also added that eating healthily was key to Jessica getting the look she needed for the role.
She said: "The secret to have a great bod and not having to kill yourself to look good is eating right. That's a strong point of Jess's. She's motivated nutritionally, and she eats a balanced diet of salads and proteins.
"If you're eating right, that's more than half the battle."