When an ancient Incan Quipu is translated, it appears to confirm the existence of the fabled city of gold, El Dorado. Pang-yi and Professor Ji head to Peru to investigate this finding, only to learn that the researcher who translated the Quipu has disappeared. Together with a direct descendant of the Inca, the treasure hunters set out to solve the mystery but what awaits them in the heart of the Inca empire.