A young woman, Lucy gets caught up in the drug trafficking world. The drug she traffics is a drug that can unleash the ability to use 100% of a person's brain functionality. Lucy uses the drug and as she gains more access to her brain she becomes a ruthless killer.
I was with this movie until she gained about 60-70% of her brain capacity. After that, it got weird. Time and space stopped mattering, and I think you needed to be much smarter than I am to understand where they were going with it. However, you get 90 minutes of looking at Scarlett Johansson, so there's a trade off.