The King's Fifth  The King's Fifth (1966) is a children's historical novel by Scott O'Dell that was the inspiration for the cartoon TV series "The Mysterious Cities of Gold". It describes, from the point of view of a teenage Spanish Conquistador, how the European search for gold in the New World of the Americas affected people's lives and minds. The title refers to the one fifth share of spoils expected by the Spanish Crown. The story takes place in a time when the Spanish adventurers known as Conquistadors colonised the New World of the Americas in search of the mythical gold treasures of the dethroned Native Americans. The book was the inspiration for the 1982-1983 French cartoon TV series "Les Mystérieuses Cités d'or "(The Mysterious Cities of Gold)". A few of the central characters take their names from the book, the high-level quest (searching for the Cities of Gold) is the same, and the "golden lake" scene from the book is also present in the cartoon, but the similarities end there (the cartoon has motifs of fantasy and science fiction). The cartoon is set in South America, whereas the expedition in the book explores New Mexico and Arizona in North America. The book is also a slight influence in the Choose Your Own Adventure Time Machine's 1987 book "Quest for the Cities of Gold," as the reader meets Esteban at different points.