The crazed scientist Dr. Morphos has lured Tarzan to his evil island where the inhabitants are experimental animals being turned into strange-looking creatures. There he is captured and chosen to be part of the main experiment tests.
The evil twin of the Wazdon Chief Denat has assumed his identity and has been having the tribesmen mine for gold in a volcano. It is up to Tarzan to stop him.
Fana the Huntress has come to the Jungle with her white tiger Pasha to capture Jad-bal-ja, the Golden Lion, an orphan that Tarzan raised from a cub, but she is soon captured by the Bolgani.
Tarzan rescues a young girl and takes her back to her homeland. When they are caught in a storm, Tarzan is captured and taken to a virtual city of gold.
After dealing with a gorilla named Terkoz, Tarzan meets Jane Porter and her father Professor Archimedes Q. Porter after falling victim to a mutiny during an archaeological expedition to the lost city of Cowloon.
A greedy fortune hunter hires a professor to create a robot identical to Tarzan and uses it to sow distrust between the real Tarzan and his animal friends in the jungle.