Emma went with her family to explore the world. However, by chance, it turns out that the new girl, Bella, who has come to the city, is also a mermaid, and her power is to turn water into jelly and a crystalline substance. The girls make friends. The new boy, Will, discovering the cave on the island of Mako, aims for the discovery of a strange phenomenon that takes place there. When Will discovers Bella's secret, she also decides to keep him. Lewis is going to America on a scholarship. The girls save the Earth from destruction, reflect the meteorite, thus changing the direction of his flight. Bella meets Will, Lewis returns, and Rikki improve their relationship with Zan.