Edgar Rice Burroughs
English
The story begins with Lieutenant Albert Werper, a disgraced Belgian officer exiled to a Congo post. Driven by isolation and resentment, he murders his captain and flees into the jungle, only to be found by the Arab raider Achmet Zek. Werper, seeing an opportunity to save himself, joins Achmet Zek's band, eventually becoming privy to the Arab's plan to target Tarzan. Achmet Zek desires revenge and wealth from Tarzan, contemplating the abduction of Tarzan's wife, Jane Clayton, for ransom. Meanwhile, Tarzan, living as Lord Greystoke, faces financial ruin due to a company failure. He decides to return to the lost city of Opar to retrieve more treasure. Werper, disguised as a French hunter, gains entrance to Tarzan's home and overhears his plan to visit Opar. Werper then informs Achmet Zek, who begins to move his forces towards the Greystoke estate. Tarzan, stripped of his civilized veneer and embracing his primal nature, journeys towards Opar, accompanied by loyal Waziri warriors. During his trek, he encounters a dying witch-doctor who warns him of future dangers. Tarzan also unknowingly parts ways with Werper, who is secretly trailing him. In Opar, Tarzan, still suffering from amnesia caused by an earthquake that blocked his way, stumbles upon a hidden jewel room. He collects the gems, unaware of their value, and then, after a brutal fight with a lion, he encounters La, the High Priestess of Opar, who recognizes him and declares her love. Tarzan, however, does not recognize her and, aided by Werper, escapes Opar, leaving La enraged and vowing revenge. Back in Opar, Jane Clayton is attacked by Achmet Zek's raiders. Mugambi, Tarzan's loyal servant, attempts to defend her but is overwhelmed and left for dead. Jane Clayton is captured and taken north by Achmet Zek. Meanwhile, Tarzan, still suffering from amnesia, wanders the jungle, accidentally finding and then losing the jewels he had collected. He also encounters his former tribe of apes and engages in a battle with a rhinoceros. Mugambi, having survived his injuries, tracks the Arabs and eventually encounters Werper, who, having escaped from Abyssinian captors, makes his way back to Achmet Zek's camp. Werper, now in possession of the jewels, convinces Mohammed Beyd, Achmet Zek's lieutenant, to betray his chief, planning to escape with the jewels and Jane Clayton. However, Taglat, one of the apes, also takes an interest in Jane Clayton, leading to a chaotic escape attempt from the Arab camp for Jane, Tarzan, and the apes. During the ensuing chaos, Tarzan’s memory begins to return. He learns that the jewels were a deception by Mugambi, and the true jewels were stolen from him. Tarzan, with the help of his ape companions, attempts to locate Werper and the jewels. Werper, meanwhile, attempts to betray Mohammed Beyd, only to be outwitted and lose the jewels again, this time to Achmet Zek. Tarzan, still seeking the jewels and his wife, finds the camp in disarray after a lion attack. He rescues Jane Clayton, but Werper escapes with the jewels. Tarzan, with Jane, eventually makes his way back to the Waziri, only to discover that their home has been destroyed by Achmet Zek. Mugambi, however, has survived and helps them track the Arabs. The story culminates in a final confrontation where the true jewels are recovered, Werper meets his end, and Tarzan's memory is fully restored as he and Jane return to their rebuilt home.