The main character of the five stories that are included in this book is Estrellita, a restless starfish who never tires of exploring both the undersea world and dry land. In the first story, Estrellita, on one of her many trips to the beach, confuses the stars shining in the night sky with her sisters and friends who live at the bottom of the sea. In the second of her exploits, she is joined by her dolphin friend, Delfín, and together they go to see the mayor of a coastal town in order to protest about the pollution caused by a local factory and its serious effects on the animals that inhabit the depths of the sea. The third story tells of the adventures Estrellita has when riding on the back of her friend Tiburón, the shark. In the fourth tale, she climbs onto a seagull and flies up to the big black clouds to ask them to put a stop to the downpour that is falling on the beach. The last story narrates the trip that Estrellita makes from the sea up into the mountains.
The idea behind this book is to bring children into contact with the social and natural environment in an informal, amusing way.