The story opens with a description of the "power stone" of harmony and harmony in the world. The power stone is the unity of the seven seas. The seven seas are atlantis, crystal, atmospheric, and ocean. Atmospheric is "the power of fury" and ocean is the power of sorrow. The world is divided into seven regions, each with its own power stone. One island, called the "happy island," has a power stone of harmony. The happy island is named after a mermaid who has survived a shipwreck. The mermaid is named Maria, and she is the manager of the band of crystal. Maria tells her that the band is planning to rehearse in a few days. She also tells Maria that she has some news. The band has been invited to perform in the four islands.