Amu is a shy girl, except that's not what everyone at school sees. They see a super-cool girl that they could never hope to be on the same level as. But when Amu one night wishes to have the courage to be herself, she wakes up the next morning with three colorful eggs beside her. When the first of the the three hatch, she learns they are her Guardian Characters, and that they can change her character to the "self she wants to be". When she is asked to join the school Guardians for a tea party, she learns they each have their own Guardian Character as well! With some reluctance, Amu steps in to take the Joker chair, also known as the trump card of the Guardians, to help find and protect something called the Embryo, which can supposedly grant the holder a wish.