Tarzan returns to Opar, the source of the gold where a lost colony of fabled Atlantis is located, in order to make good on some financial reverses he has recently suffered. While Atlantis itself sank beneath the waves thousands of years ago, the workers of Opar continued to mine all of the gold, which means there is a rather huge stockpile but which is now lost to the memory of the Oparians and only Tarzan knows its secret location. A greedy, outlawed Belgian army officer, Albert Werper, in the employ of a criminal Arab, secretly follows Tarzan to Opar. There, Tarzan loses his memory after being struck on the head by a falling rock in the treasure room during an earthquake. On encountering La, the high priestess who is the servant of the Flaming God of Opar, and who is also very beautiful, Tarzan once again rejects her love which enrages her and she tries to have him killed; she had fallen in love with the apeman during their first encounter and La and her high priests are not going to allow Tarzan to escape their sacrificial knives this time. In the meanwhile, Jane has been kidnapped by the Arab and wonders what is keeping her husband from once again coming to her rescue.

エドガー・ライス・バローズが描く本作の真髄は、記憶を失い野性へと回帰したターザンの魂の彷徨にあります。文明と野蛮、富と愛が伝説の黄金都市を舞台に交錯し、読者の根源的な冒険心を揺さぶります。高僧ラとの愛憎劇は、単なる活劇を超えて人間性の本質を問う文学的深みを備えています。 映像化作品が視覚的な迫力を追求する一方で、原作はターザンの内面的な葛藤や神話的な情景を緻密に描き出します。文字から立ち上がる野性の息遣いは、映像による直接的な刺激を補完し、より重層的な読書体験をもたらします。想像力で補完される未踏の地の神秘こそ、本作を永遠の古典たらしめる魅力なのです。