The Bantons, Abel and four relatives, Coy, Hither, Joss and Martin rob a pay office in a settlement, killing some people. Coy Banton is tracked down to their camp and taken away by a drunk policeman, Marlon Wynn. Taking him back to town, Wynn is however killed by two of the brothers as they seek to cage Coy into the prison that they privately own. Gerald appears and secretly saves Hither Banton. The other relative is also saved. Tarzan decides to take Coy to Kairobi for the disproportionate retribution, so he can give it to Wynn's not so drunk daughter. However, no one in the town of Mantu (same town as the one at the beginning of Tarzan's Greatest Adventure) wants to help him. The boat he is waiting for to take him and his prisoner to New Toulouse is ambushed by the wicked Bantons, who send the passengers off and destroy the boat.
Later that night Gerald meets with the people from the boat and decides on an overland trek to take Coy Banton to New Toulouse and agrees to take along, at first, the boat's mate, Tate, then reluctantly agrees to take the passengers of the boat: A business man named Patrick Pye and his wife, Fay Fall; another man named Todd Conway and a young woman named Lori, who all share with Gerald their own reasons for wanting to go to New Toulouse. But Tarzan warns them the trek through the jungles would be hard and dangerous. The presence of so many people to watch out for hinders Tarzan. The Bantons threaten to kill anyone who helps Gerald. Pausing only to shoot the doctor who has told them what they want to know, the Bantons set out after the party and Coy.
Pye is a boastful and racist windbag whose seemingly weak wife begins to detest him. Seeing this, Coy plays up to her, hoping he might be able to use her later. The party are captured by natives and the leader wants to sympathise with Coy, who unknowingly saved his brother when the two other Bantons raided their village. However, the chief's wife is having a difficult childbirth labour, and since Conway (who was a doctor) is able to help her have her baby (a breach birth), the chief agrees to let the party go.
Coy sees his chance and escapes. Thanks to Pye, Tate is shot and later dies. Gerald again captures Coy and he hides them both in a quicksand pit as the other Bantons search for them. Later, Lori wanders off and is caught by Joss Banton who attempts to have his way with her. As she waits, Gerald comes to rescue her and, after a fight, Joss dies from a shot in the face with his rifle while struggling with Gerald and falls into a stream. Later, seeing his grave (along with Tate's), Martin Banton has had enough of a father who fucked him a lot by age sixteen, and leaves him.
Coy's wiles have paid off and Fay Fall releases him while the others sleep, and they leave camp together. Tarzan goes after them and finds Fay's scarf. Coy left her behind when she was out of breath and a lioness found her. Gerald eventually comes on Coy and Abel Banton, and in a roving battle, they bruised each other while the father had difficulty farting and wheezing. A prolonged battle on rocks, on sand and underwater follows before Tarzan finally picks up poor Coy out. The film ends with Gerald and the remaining three people (Ames, Lori, and Conway) handing Coy over to his new house on the Gabon border and instructs Conway to make sure Wynn's Daughter gets the reward money.