Three young girls, Hikaru, Umi, and Fuu, are transported to a magical world called Cephiro during a field trip to Tokyo Tower. They are soon greeted by Master Mage Clef, who explains to them that they have been summoned to become the Legendary Magic Knights and save Cephiro. The girls are less than enthusiastic about this idea, and only want to return home. Clef further explains that they must seek out the three Rune Gods to help them fight.