When the Professor's rival, Samuel T. Philander, visits Africa, he must come up with something spectacular to become famous on before Philander. That's when Tarzan tells them about Pellucidar, an underground world where dinosaurs live. However, Philander follows them there and takes pictures of the dinosaurs. The Professor, having no camera with him, attempts to best Philander by taking something else with him.

The Professor learns about a spiritual silver ape that, supposedly, cures the injured of the jungle. Not believing this is a spiritual creature, he plans to study it more. But when Philander steals his notes and finds out about the ape, he plans to capture it.

Philander returns to Africa with two British thugs to capture "Tarzan: The Missing Link" in a last-ditch effort to pay off the thugs. While there, they meet up with the Professor and Philander attempts to convince the thugs that the Professor is Tarzan.

A writer named Ed is in desperate need of some inspiration for his next novel. He finds it while walking down the street in the form of a newspaper article about Tarzan, "The Missing Link". He begins tracking down various leads to Tarzan's whereabouts, including Tarzan's friends and enemies. They all tell Ed of their first encounters with Tarzan, prompting Ed to head out into the jungle to find Tarzan himself.