Tarzan and Jane are returning home from visiting the Waziri Village via a river boat piloted by Hugo and Hooft. When they land, they notice that Dumont's trading post is really growing and modernizing. They also notice that the jungle is eerily quiet with no animal sounds to be heard. When they return home they find the tree house is in shambles as is the professor's camp and he has disappeared. Terk and Tantor burst into the camp complaining of a ringing in their heads and acting violently. Soon Tarzan and Jane are on the run for their lives as all of the jungle animals have turned against them in a psychotic rage. Later, while hiding from the animals, Tarzan discovers that the ringing the animals hear is due to a recent radio broadcasting tower built at Dumont's trading post. After Tarzan tricks them into destroying the tower, the animals return to their old selves again. (thetvdb.com)