Spanish novel.Juvenile fiction. Related to nature conservation. A dolphin will lead a group of young heroes to save the world from a psychopathic man. He uses genius children to control a strange material found at the sea. The crystals can change the atomic charges of all the materials containing silicium and destroy it. Silicium is an important material in crystal and sand. This means cars, buildings, lights, almost everything, could be destroyed. With this crystals Luke will try to control the world.