Girlfight is a dramatic film that stars Michelle Rodriguez. Rodriguez plays Diana Guzman, a young woman who is facing a lot of difficulties in her life. Diana has a temper and a lot of anger so she tries to use them in positive ways. Diana is struggling after the death of her mother. School is torturous for her as she does not get along with the so-called popular girls. She ends up getting expelled from school for fighting. She gets her first exposure to boxing when she sees her younger brother doing it. She decides to enter the male-dominated world of professional boxing as a way to deal with her problems. Her father is an extremely abusive man and he constantly tells Diana that she cannot succeed. A lot of the trainers that Diana meets with do not feel as if she will be able to do well either. However, Diana begins to attract attention when one of the boxers starts picking on her younger brother and she knocks him out.
Diana finally meets Hector, who has been training her younger brother, and gets him to agree to train her as well. Although Hector doesn't believe Diana can box at first, he eventually begins to feel that she does have talent and begins to push her towards success. Diana needs money to pay for her lessons so she tries to trick her father into giving her an allowance. He is not fooled and refuses to give her any money.
Diana spends a lot of time training with another young fighter, Adrian. Adrian and Diana develop feelings for one another which are complicated by the fact that Adrian has a girlfriend. Diana also struggles in the boxing world because she has no female competition. Although she fights men, that can only take her so far. However, boxing becomes a positive outlet for Diana and she begins to grow and mature as a young woman.