On a school trip to Tokyo Tower, three strangers, Hikaru Shidou, Umi Ryuuzaki, and Fuu Hououji, are brought together by fate. An unexpected burst of light and a stranger's plea for help to save a realm called "Cephiro" propels the middle school girls on a fantastical adventure. They are taken to an unfamiliar world by a gigantic fish and encounter Master Mage Clef. Clef informs the girls that Princess Emeraude has called upon them to become Magic Knights and fulfill their destiny. Their mission is to restore peace and balance to the chaotic land of Cephiro. Previously, Princess Emeraude was the pillar of stability, but High Priest Zagato has captured her, causing turmoil. Initially hesitant, the Magic Knights eventually accept Clef's words and embark on a mission to free Cephiro from sinister forces.