A blue bus drives through various country roads to arrive at the small town of Sao Sebastiao in the Amazon jungle, presumably in Brazil. Prof. Ibanez and his daughter are passengers and exit through a crowd of locals who have come to see the arrivals. The desk clerk at the one local hotel says he has only one room instead of two because of the arrival of some Americans. The Professor asks the hotel clerk about the two plane seats reserved for he and his daughter the next day. One man and two attractive women descend the stairs and the hotel clerk says they are a photographer and his two models from San Pablo. Back outside, Kevin Hall (Michael Sopkiw) arrives on a truck. He has a large trunk full of bones from primitive animals. He has little money and the kids make fun of him. He requests a room from the hotel clerk but is denied. He offers an American Express card. Jump cut to a photo shoot with the photographer (), the two models (Belinda and Monica) and indigenous extras. Back at the hotel, it is evening and there is a cock-fight that continues through the next several scenes. A South American woman dressed up to look like Marilyn Monroe (Betty Heinz) is nagging her ex-captain ex-husband about his inability to sexually satisfy her, while she ogles Hall. A French pilot tells the ex-husband that the professor wants to make a stop at the Valley of the Dinosaurs, even though it is part of the Aquira (sp) Indian reservation and he could lose his license. Hall overhears this conversation. The French pilot has a drink with Hall and "guesses" Hall is a bone hunter. Hall says he studies the bones of prehistoric creatures. He too wants to go to the Valley of the Dinosaurs. He later says he is with the Boston Institute of Palentology. He knows of Professor Pedro Ibanez. A small man grabs and undresses one of the models, Monica (Maria Reis) and Hall pulls the man off her and pushes him away. Hall is approached by the mans two very tall muscular brothers. Hall crashes a chair over the two giants, who are unaffected. Later, Hall is recovering from his injuries and lying down. Monica, the assaulted woman, shows up to thank him. They kiss and make love. Later, Hall makes his case to Prof. Pedro Ibañez (Leonid Bayer) and his daughter to be allowed to join the flight. The flight takes off with the pilot, Hall, the two Ibanez's, the ex husband and Marilyn Monroe wife, the photographer, and the two models. The plane crashes in the jungle with three casualties, the professor, the pilot, and Monica. The six survivors, three men and three women, begin their walk through the jungle. They encounter skulls in the jungle and leaches and snakes and dissension and see natives wilding. At one point, Hall with a gun and John with a machete face off. Johns's wife Betty laughs and urges Hall to shoot. Piranha attack the group and chew off most of the right shin of the photographer, and John then finishes him off. In the ensuing melee, the group is separated and wife Betty sinks in quicksand. Ex-husband John is shot by Indians, who cut out his heart. Leaving Hall, model __, and daughter Monica as the only survivors. The two women are captured and bound in the Indian village, which Hall attempts a rescue. Children taunt the girls. The women are stripped and dressed and brought to a large stone alter where a native with a crocodile glove gropes them. Hall returns with a rifle and rescues the women and they escape in a canoe. The three travel some distance in the dugout canoe along the river. The Aquara try to net the entire canoe on the river, but fail. The three pull to shore and Hall and __ go off to search for food. While making out in the dirt, they discover dinosaur tracks. They are then ambushed by a mysterious white stranger (China). He's a bit lecherous. He is leader of a mining camp on the river of a dozen or so people. Kevin is knocked out by a gun barely to the back. Maria is interested in the girls, but China says hands off. A shirtless Hall is tied up next to the pig pen. China explains that the secret of the mining operation cannot be compromised. He kicks Hall and warns him against insubordination. The pigs attack. Maria continues with the girls, licking the blood off her breasts. Belinda (Susie Hahn) is then shot in the back by the sadistic China. After sunset, the pigs return to attack Halls arm, but bite through the ropes holding him, thereby releasing him. In a taught battle, China has to decide between shooting Kevin or a rattlesnake. He chooses to shoot the snake, and Kevin spears him. Hall frees the enslaved miners and then rigs explosives and blows up the entire mining camp. A helicopter lands and Hall and __ steal it and make their escape, as the two profess love to one another. P.S. no dinosaurs are ever seen.