The heroine of this tale is Mariella, a young and fearless mermaid who lives in the ocean with her parents. One day, she decides she wants to travel and discover new horizons. After much preparation, she leaves to explore the ocean depths she has heard so much about, and which seem to call to her. During her journey, she meets a multitude of sea creatures each more endearing than the last. Join Mariella on her enchanting voyage as she grows into a wiser, greater person.