The vast ocean sings to me. I must go and conquer it!

Our last summer at Seisho Music Academy―― With the 101st Seisho Festival "Starlight" coming up, we the students of the 99th class take up the challenge to perform "El Dorado", an oceanic epic that Japan is proud of, for our summer performance.

The exiled admiral, Salvatore Guglie. The heir to a royal Spanish family, Alejandro Javier Cavallero Cruz. Who will "we" choose... between the "two protagonists" of this story?

The curtains rise upon the "next stage", where students of the 99th class take on the vast ocean.