Based on an idea that amuses neuroscientists — that human beings use only ten percent of their brain — this violent fantasy follows Scarlett Johansson as Lucy, a student forced by a Korean drug lord (Choi Min-sik) to carry a new narcotic in her abdomen that, when it is accidentally released into her system, begins to awaken the supposedly dormant 90% of her gray matter. Along with her ever-increasing powers of the mind comes the knowledge that she will soon die if she doesn’t get more of the drug, a mission the drug lord is determined to thwart. Besson includes a few funny metaphorical asides by way of cuts to the animal kingdom, which, along with the gun-play and car crashes, are meant to divert us from the absurdity of the characters and story. Morgan Freeman, for instance, plays a scientist whose childish daydreams of expanded brain-use are treated as respectable scientific theories; meanwhile, Lucy’s incredible new intelligence includes a convenient black hole in the area of her battle with the drug lord. Lucy’s self-absorption is understandable, but her amoral anarchism is not. For mavens of mayhem only.