15-year-old Emi Kimura and her little brother Takeo have spent most of their life at a flower shop with the kind owner ever since their parents dropped them off there when they were little. Life has been good for them and Emi helps her friend April O'Neil who is a journalist to investigate crime scenes. One night, she spots four mutant turtles watching a movie and she becomes friends with them. But when a mutant army is planning to mutate New York, Emi must help the brothers and April stop them before they take over the city and along the way, she steals the heart of a certain red masked turtle.