The stories are in the world of Salacia, a hidden kingdom under the sea, full of princes and princesses from different animal species. Fearing an inevitable conflict with the people of Terra Firma, the kings and queens of the sea forbid their daughters and sons to have any contact with the surface people who are completely unaware of the existence of Salacia. Three princesses, the show's protagonists, live, go to school and play together as friends: Polvina, the Octopus Kingdom princess; Tubarina, the Shark Kingdom princess and Ester, the Starfish Kingdom princess living unraveling the mysteries of Salacia.