In Central America, a little native boy, Ramel, is abducted by Vinaro, a madman who believes the child to be the sole link to a lost Aztec city of gold. Vinaro uses one of his diabolical explosive mechanisms to eliminate police and army officials; and the legendary Tarzan is flown in to help locate the jungle city, rescue the boy, and bring Vinaro to justice.

Tarzan is joined by a reporter and her fiance on a journey to find a boy who was abandoned in the jungle six years earlier. The search party must also battle an evil native, who is out to kill the boy and take over as chief of his brother's tribe.

Tarzan is summoned to Brazil by an old friend to stop an evil tribal cult from destroying native villages and enslaving the survivors. The Lord of the Jungle is accompanied on his quest by a pretty blonde doctor, a boy and a grizzled sea captain.