Sophie and Bongo arrive on an unknown island in the Canaries, this Spanish archipelago lost among Morocco and Mauritania.
The Gomera island is a wild land, which has maintained a strange language for centuries : Silbo, the only whistled language in the world. A curious legacy of idegenious people – the Guanches – who lived on the island before the Spanish arrived, that is still taught in school. With young students from Gomera, and Lilto the shepherd, Sophie will learn the basics of this whistled language.
Up on the hills of the island, another experience awaits Sophie : « horizontal rain », a natural wonder generated by the primary forest called the Laurisilva, one of the last forest replicas covering Europe during the tertiary era.
Finally at Vueltas, the oldest fishing port of the island, tuna fishermen have a surprise for Sophie : an exceptional encounter with dolphins, so close that Sophie will be able to hear and smell their breath as they swim around the boat.