Scarlett Johanssen is a young woman who gets caught up in a bad drug deal with her scummy boyfriend. The synthetic drug turns her into a super human with a much developed brain, and she turns on her enemies.
Morgan Freeman is a prof. that she wants to contact and let him know what it is like to use 100% of the human mind. her body is able to change shapes and her mind can control all around her, making her impossible to stop or control.
The end of the film is a little over the top, but it was just to show off effects and you have to do that with today's audiences. Scarlett does a good job of conveying the pain of knowing you are turning into something more than human, especially in the scene where she calls her mother.
I have worked with Scarlett, but that was way back when she was a child and has she come a long way. If you like modern horror films, you might want to check this out.