Searching for the Cities of Gold, Esteban and his friends cross a high plateau up in the Andes. Near Lake Titicaca, they are attacked by the Urubus, a tribe of giants. Tao invents a submarine, and they capture Karuga, chief of the tribe, and hold him prisoner. Karuga tells them that there's a City of Gold on a mountain, guarded by the earth goddess, Pachamama.