Description: At the end of the previous novel (#4) Tarzan (John Clayton) and Jane's son, Jack a.k.a. Korak, has come into adulthood. John (Tarzan) and Jane Clayton have left London and returned to their Waziri ranch, some distance from Tarzan's original stomping grounds in Africa (where Jack will find them in novel #4).
John Clayton finds that his fortunes have been embezzled, so he decides to return to the lost city of Opar, where he procured a large supply of gold from their forgotten vaults and reinforced his family fortune (in novel #2).