This is the 11th book in the 24-book series of the character Tarzan. It begins something of a departure from Tarzan's previous adventures, which generally concerned his jungle family and events nearby. Burroughs now introduces wider ranging adventures, with lost kingdoms, hidden riches, and invaders from afar. It is believed that no other figure in the fantasy world has had such enduring impact as has Tarzan. - Summary by Robert Rollins