Rafa and his sister Matilde, accompanied by the terrifying Viruñas, embark on an adventure fighting against the evil Lope de Aguirre, a bloodthirsty Spanish conqueror who returns as a ghost, after so many centuries, to try to do what he could not do in life: take El Dorado and its great treasures, and to do that he must catch the phantoms that have kept the traditional legends, and therefore, the popular memory, alive. Readers can develop literary analysis skills and deepen their understanding of the cultural roots of the Americas as they read this engaging adventure story.