Hidden somewhere beyond the highest clouds is the castle of Destino, a school for very special students. They're the Melowies, little unicorns born with a symbol on their wings and a hidden magical power.
The Melowies finally start the Art of Powers class which teaches them to strengthen the power they were born with. Clio, having been left at Destino when she was born, does not know the realm she is from and does not know what her power is. She must take lessons in all of the realms in order to find out which she belongs to.
The Melowies are required to perform a musical in front of all of Destino. Selene does not want to participate because she made a fool of herself the last time she performed publicly. With a little encouragement from her friends she auditions and wins the role of the moon!