In the city of Minato Mirai in Yokohama, the news of Fusion's defeat by the Pretty Cures is the hottest topic in town! Girls everywhere are dressing up and acting as their favorite Cures. Only Sakagami Ayumi, the new transfer student, is alone by herself.

On her way home from school, Ayumi encounters a strange creature. After naming it Fu-Chan, Ayumi and the creature soon become good friends. However, Fu-Chan is actually a piece of Fusion, and holds the power of darkness. In an effort to make Ayumi happy, Fu-chan swallows up everything that Ayumi dislikes, creating chaos in school and throughout the city!

To help bring across Ayumi's true feelings to Fu-Chan, all 28 Pretty Cures gather once more. When everyone's power comes together, a miraculous light starts to shine.