Frantically hacking his way through the undergrowth, Markham comes to a ridge in a clearing that reveals before him an endless valley of dense jungle. The father, Bill Markham, spends the next ten years searching in vain for the kidnapped boy. Shortly after dawn, Markham, in hot pursuit and low on ammunition, stumbles into the foot of a waterfall and sees a young Indian underneath the falls gathering stones. Bill himself has become well versed in tribal Amazonian culture in his search for the elusive people who took his son, to the extent that he has become nearly fluent in a few local Indian dialects. However, during the attack, several members of the Invisible People are killed, including the chief, Tommé's adopted tribal father. Seeing an opportunity, the unscrupulous owners of the brothel manage to communicate to the Fierce People that if they are brought some women motioning to the adjacent jungle that they would then give the Fierce warriors all the guns and bullets they wanted.
Ford is now on the run trying to clear his name from the murder with Trey and his gang looking for his blood. During the journey, the two tribesmen meet and are helped along by two other young men who are revealed to have been former members of the Bat People tribe, but who now live in the city. Coordinating his attack with the Invisible People to take place at night, while all the members of the Fierce People are wildly drunk outside the building, Markham initiates a shootout in the brothel whilst all the women are sprung from captivity. His young son, Tommy, aged seven, wanders from the cleared area to just inside the treeline where he amuses himself by feeding his picnic snacks to the large jungle ants. Soon afterward, during a particularly bad storm, Markham places demolition explosives at key points along the dam, blowing it up during the peak of the rains. Regardless of the arrow, Markham pursues them, calling upon all the nearby construction workers to help. The construction requires large areas of forest to be cleared, even more to be flooded.
As the unstoppable Nazi forces roll across Western Europe and the threat of invasion is imminent, and with an unprepared public, a skeptical King, and his own party plotting against him, Churchill must withstand his darkest hour, rally a nation, and attempt to change the course of world history. Tommy, or Tommé as he is now called, has become part of the tribe that he lives with, adopting their language, culture and way of life. When coming back to their village from taking Markham back home, Tommé and his friends in the tribe discover to their horror that the village has been violently raided, many have been killed and all their young women are missing. In the aftermath of this event, Tommé becomes chief of the tribe. The story jumps ahead some ten years. Later, at a seedy brothel and cantina on the edge of the construction zone, the Fierce People wander from the jungle with the M4 in hand to essentially ask someone from civilisation how to work the thing.
The tribe even includes a few new members in the two young men from the Bat People who had helped Tommé earlier. When the film opens, Markham has taken his family to the edge of the forest for a picnic to show them the jungle and the progress of the dam's construction. After 35 years, Evan escapes from a mental institution and returns to town for revenge, killing off residents one by one. Tommé and his father fight off the Fierce warriors and manage to escape downriver, but Markham loses his carbine in the process. The Fierce People are a hostile tribe of cannibal warriors, who ironically had been displaced from their own lands years earlier by the beginning of the dam's construction.
It is then discovered that the Fierce People have sold them all to the brothel for rifles and liquor. For ten years, engineer Bill Markham has searched tirelessly for his son Tommy who disappeared from the edge of the Brazilian rainforest. Tommé is depicted going through rituals of manhood and courtship, becoming involved with a beautiful member of the tribe named Kachiri. Miraculously, he finds the boy living among the reclusive Amazon tribe who adopted him. For his son is now a grown tribesman who moves skillfully through this beautiful-but-dangerous terrain, fearful only of those who would exploit it. He comes to understand his son's transformation and the tribe's way of life, forging a begrudging respect for the chief who took him as a child.
Boothe's son played by Charlie Boorman - son of director John Boorman is kidnapped by a rain forest tribe, and raised as one of their own. The tribesman who took him is revealed to be the chief of the Invisible People, and has taken Tommé for his own son. With the dam washed away, Tommé and the tribe can live in relative peace for a little while longer. But when Tommy's mate Kachiri and the women of his tribe are kidnapped by a gang of white slaves to work in a brothel in the forest, Tommy searches Bill in the big city to help his tribe to rescue the female Indians. The journalist is not so lucky, and is gutted on the spot by the tribe's women. The chief is seen working himself up into a rage whilst stuffing bones and rocks into the firing chamber of the carbine in an increasingly desperate and futile attempt to make it shoot. As Markham realises his son has just been taken, a warning shot from an unseen archer lands in a tree near his head.
Boothe's son played by Charlie Boorman - son of director John Boorman is kidnapped by a rain forest tribe, and raised as one of their own. . Back home with the Invisible People, Markham spends time recovering from his injuries and fighting off a fever. The only clue Markham has to seek out answers is the arrow that was originally shot at him when his son was abducted. Boothe continues to look for him and after many trials and adventures, stumbles upon him. However, Markham and his journalist companion, whose cynicism and sarcasm concerning indigenous peoples is beginning to wear on him, set off for a likely place along the river where they intend to camp and set off fireworks and bottle rockets to attract the attention of any uncontacted but curious tribes in the region.
The chief of the tribe informs Tommé that the quest will be dangerous, as the Fierce People have moved into the area. Based on a true story, Powers Boothe plays an American dam engineer in Brazil. Tommé and his best friend from the tribe then embark upon a harrowing quest into the city, where he will find his old home according to his childhood memory, and ask his father for help. It is then that an Indian from one of the indigenous tribes known as the Invisible People notices him, and is struck by the boy's blonde hair and bright green eyes, which are the colour of the forest. Markham then flees the jeering Fierce People into the jungle, firing bursts from his carbine into the darkness behind him. Right before he shoots, the young Indian steps forward toward Markham and is revealed to be Tommé, and the two instantly recognise each other. They are now coming into uncomfortably close proximity to the Invisible People.