Clair-de-Lune has lived all her life with her grandmother at the top of a very tall, very narrow, very old building. Her mother, a great ballerina, died on stage when Clair-de-Lune was a baby. Ever since that day, Clair-de-Lune has not uttered a word.
Then she meets tiny, brave Bonaventure, a talking dancer-mouse, who takes her to the mysterious monastery hidden in a secret fold of Clair-de-Lune's apartment building.
But this is only the beginning of the journey for Clair-de-Lune, and she could never have dreamed what adventures were still to come.