Jungle explorer Jim Taylor agrees to lead an expedition to locate the source of gold and emeralds found in the Purus River, a tributary leading to the Amazon. Jim and his three assistants set off with twenty-five bearers, as well as the wealthy sponsor, rugged Craig Manners, owner of a pharmaceutical company. All does not go well as "El Tigre", the notorious bandit and kidnapper harasses them. The group rescues four hostages being held by El Tigre,...