Mew Mew Power

In Tokyo, Japan, a young girl named Ichigo Momomiya attends an endangered species exhibit with her "crush" Masaya Aoyama. After an earthquake, Ichigo and four other girls are bathed in a strange light. A cat appears before Ichigo, then merges with her. The next day, she begins acting like a cat and making cat puns. After meeting Ryô Shirogane and Keiichirô Akasaka, Ichigo learns that she was infused with the DNA of the Iriomote cat. Ryou and Keiichirou explain that this allows her to transform into Mew Ichigo, a powerful heroic cat girl. She is ordered to defeat Chimera Animas—alien parasites which infect animals and turn them into monsters. Ryou and Keiichirou instruct Ichigo to find the four other girls from the exhibit—the remaining Mew Mews.

The first Mew Mew Ichigo encounters is Minto Aizawa, a spoiled, wealthy girl and ballerina who is infused with the genes of the blue lorikeet;[n 1] Retasu Midorikawa, a shy but smart girl who endures constant bullying from three girls and absorbs the genes of the finless porpoise; a hyper and yet young girl named Bu-Ling Huang who receives the genes of the golden lion tamarin; and Zakuro Fujiwara, a professional actress and model infused with the genes of the gray wolf.

The five Mew Mews battle the Chimera Animas and their alien controllers Quiche, Pie and Tart. Quiche falls in love with Ichigo where he tries to gain her love despite the fact that he is trying to eliminate the other Mew Mews. Pie and Tart later join Quiche in trying to destroy the Mew Mews.

As the fighting intensifies, the Mew Mews are tasked with finding "Mew Aqua", a material created from pure water that contains immense power for combating the alien attacks and can be sensed by the Mew Mews. During a battle with Quiche at an aquarium, Ichigo is in danger of losing when the mysterious Blue Knight appears and rescues her. He returns periodically throughout the series, protecting Ichigo from various dangers. It is later revealed that the Blue Knight is in fact Masaya. Shortly after this discovery, Masaya collapses and transforms again. This time, he transforms into Deep Blue, the alien leader who wants to destroy humanity. After explaining to Ichigo that Masaya was a false form for temporary use, Deep Blue attacks the Mew Mews. Pie and Tart try to stop the other mew mews while Ichigo goes after Deep Blue. He and Quiche battle and Deep Blue wins. Masaya's personality briefly reappears and he uses the Mew Aqua inside Deep Blue to save Ichigo and tokyo, killing himself in the process. Crying over his body, Ichigo pours her power into Masaya to save his life, losing her own in the process. Masaya kisses her, changing her back to a human and revives her. Ryou gives Pie the remaining Mew Aqua to save the aliens' world, after which Quiche, Pie, and Tart say their goodbyes and return to their own world.