NEW YORK (Reuters) - Gun-toting thugs and a vicious Asian mob boss are no match for the brawn and brain of French director Luc Besson's super-powered heroine in his sci-fi, action thriller "Lucy."

Besson is known for creating strong female characters in "La Femme Nikita" and "The Fifth Element." But he goes a step further in "Lucy," which opens in theaters in theUnited States on Friday, with an American student in Taipei who becomes invincible after the full power of her brain is unleashed.

Scarlett Johansson ("The Avengers") is Lucy, a woman tricked by a boyfriend into delivering a suitcase and becomes one of several unwilling drug mules dispatched around the globe by Asian mobsters.

After a brutal beating, the powerful synthetic compound implanted in her stomach seeps into her body and gradually lets her access more and more of her brain power.

"I think it is such an interesting imagination Luc has going on there," said Oscar-winning actor Morgan Freeman ("Million Dollar Baby"), who as Paris-based neurologist Professor Norman helps Lucy cope with the startling changes in her mind and body.

Norman has been studying the brain for most of his life, researching what would happen if humans could use more than just 10 or 20 percent of it.

"We always think and hear terms like, 'We only use 10 percent of our brains' but did anyone ever imagine what it would be like if you could use more? So here comes Luc imaging what could happen if you could use more," Freeman added.

Writer/director Besson, who won France's Cesar award in 1998 for "The Fifth Element," had been toying with the idea of making a film about a person with super-human intelligence for a decade. But he felt he needed to find the right balance between reality and science fiction.

With stunning visual effects Besson shows how Lucy's senses are heightened and how she develops super-human powers and the ability to control matter. As her intelligence increases, her ability to feel emotions, empathy and pain diminish, making her a proficient assassin.

While the impact of the drug grows, Lucy travels to Paris and enlists the help of French police Capt. Pierre Del Rio, played by Egyptian actor Amr Waked (Syriana), to intercept the other drug mules.

With the Asian mobsters led by Mr. Jang, played by Korean actor Choi Min Sik, in hot pursuit Lucy leaves a trail of destruction as she takes Del Rio on a white-knuckle car chase through the streets of central Paris and a crowded flea market.

While Lucy tries to channel her intelligence with the help of Norman, French police take on the Asian mob in a gun battle at the Sorbonne.

"With Luc Besson you have a knock-down, drag-out action film but then you have one that also makes you feel and think," said Freeman. "It gives a little spark to your imagination to say 'What if? What would I do? How would it be?'"