From Nikita to Joan of Arc, director and roi of Euro-action Luc Besson has always had a penchant for women who kick ass. The heroine of his new film is no exception: Lucy (Scarlett Johansson) is a drug mule who turns on her tormentors when the experimental pharmaceuticals in her system give her increasingly omnipotent mental powers. Just imagine an action-thriller version of Flowers for Algernon. ''It's the story of this girl who was using 10 percent of her brain capacity,'' says Besson, ''and goes to using 100 percent in a couple of days, and what this does to her as a person.''

The role required Johansson to be almost entirely reactive to the craziness around her. ''She's basically a raw nerve,'' says the actress. ''Everything is happening so fast for her, and it's totally overwhelming.'' Of course, Lucy is soon doling out superpowered punishment in the mold of Alien's Ripley and The Terminator's Sarah Connor — role models Johansson appreciates. ''There's a warm spot in my heart for the woman who means business and doesn't use every opportunity to pose and look sexy in a catsuit,'' she says.