Jacqueline Hyde (2005) on Netflix

Jackie, a lonely and shy telemarketer in her late twenties, gets a phone call informing her that her grandfather has just passed away. As his only living relative, she has inherited his estate. Upon arriving at her uncle's house, Jackie discovers that he was an inventor and has a secret lab in his basement. She stumbles upon the formula that he spent his whole life working on. Due to an accident in the lab, Jackie ingests the formula and finds herself with the power to transform her body at will. This magical potion has turned Jackie Hyde into a shapeshifter! At first, Jackie thinks this is a dream come true. She can change the color of her hair, the size of her bust, even the level of her sex drive at will. This power has somehow released the animal inside and, feeling confident about herself for the first time, she goes out for a night on the town. Picking up a guy in a bar, Jackie has a one night stand. Feeling the euphoric effects of the formula wearing off, Jackie takes some more and soon discovers her more aggressive sexual side; Jacqueline, likes to be in control and wants to keep it that way! Jackie finds that she must make a decision and fight against the power of the formula before she loses her own identity for good. But the formula is like a drug and she's enjoying becoming other people, doing things she would never do, feeling things she has never felt. Each time she transforms, she loses another piece of herself until she doesn't know where the real Jackie ends and the new Jacqueline Hyde begins! In a final battle between her will and desire, her mind and her body, the final choice is made and the most powerful entity wins out!