Hikaru Shidou, Umi Ryuuzaki, and Fuu Hououji are strangers brought together by fate when they meet during a seemingly normal field trip to Tokyo Tower. Accompanied by a great flash of light, they hear a mysterious woman's plea to save "Cephiro," and the junior high heroines are suddenly swept away by a giant flying fish. Afterwards, they arrive in an unknown land, where they encounter a man called Master Mage Clef. Clef informs the girls that they were summoned by Princess Emeraude to fulfill their destinies as Magic Knights, restoring peace and balance in Cephiro. The formerly lively and peaceful land has been in disarray ever since High Priest Zagato imprisoned the princess, who acted as Cephiro's pillar of stability. The Magic Knights reluctantly accept Clef's words as truth and embark on a journey to save Cephiro from the clutches of evil. [Written by MAL Rewrite]

Soon after Hikaru, Umi, and Fuu return to Tokyo, the three of them meet at Tokyo Tower to talk. Hikaru says that she wishes they could return to Cephiro and do something good for the land that Princess Emeraude protected so dearly. Umi and Fuu agree. Suddenly, a light appears in the sky and they are transported to Cephiro. Clef explains to them that with no Pillar to keep Cephiro peaceful, it has fallen into chaos. Monsters are multiplying and the land is becoming desolate. All the remaining inhabitants of Cephiro have moved into a magical castle. Clef also tells the girls some alarming news; three other countries, Chizeta, Fahren, and Autozam are trying to invade Cephiro and take over the Pillar system for their own purposes. The girls must stop the invaders as well as the mysterious and evil Lady Debonair, who believes she is the rightful Pillar, all the while desperately hoping and searching for a new Pillar to make Cephiro into the beautiful land it once was. (Source: ANN)

Taichi Keaton is a half-British half-Japanese archeologist and SAS veteran of the Falklands War. He solves mysteries and investigates insurance fraud for Lloyd's around the world. (Source: ANN)

Mikage and Tomomi Matsunaga are Miracle Girls: they have a telepathic link with each other and can teleport when they link their little fingers. Tomomi is a sports star and has a boyfriend called Noda. Mikage is the smartest student in the school and is in love with her sempai. He moved to London to study but they still kept in touch, that is until a selfish princess called Marie decides that he should come with her back to Diammas. Back in Japan the twins are having various problems of their own. But they soon realise that there is a link between Marie, an ancient legend, and a girl they know called Emma. (Source: ANN)