Deep in the Congo jungles dwells the Okongo, a giant spider that produces a potent narcotic after ingesting certain jungle plants. Evil smugglers want the drug. They kidnap a tribe of white jungle dwellers who worship the Okongo, then force them to round up the special plants. Also being
held captive is a professor who is being sought by Weissmuller, who does battle with assorted beasts and natural disasters before confronting the smugglers and restoring peace to the region. Standard jungle genre fare.