Ichigo Momomiya's plans for a romantic evening were derailed when she fell asleep after seeing a cat in her vision, only to wake up the next day with unexpected cat-like behaviors, such as an intense craving for fish. The following day, she discovers she can transform into Mew Ichigo, a magical girl with cat ears, after saving her crush Masaya from a monster attack. Researchers Ryou Shirogane and Keiichiro Akasaka reveal she was injected with Iriomote Cat DNA to create a magical girl who can fight aliens, and there are four more girls like her who need to be found before the aliens take over. Ichigo teams up with these girls to save the world from the alien threat.