Tarzan and the Jewels of Opar

The earthquake struck when Tarzan was in the forbidden vaults of Opar -- the crypts piled high with the gold of Lost Atlantis. In the tumult, Tarzan was wounded in the head, leaving him without memory of his wife or home, only with what memory he had had as a child among the savage apes who reared him. [Facsimile reprint edition.]