When Cunda, a man living deep in the Brazilian rainforest, is bitten by a snake, he has a hallucination of four chimpanzees. Once he recovers, he is shocked to find the four chimpanzees waiting for him at home, and, believing them to be special, decides to take them to the city in order to sell them.
According to an Amazonian legend, every month, during the full moon, a Brazilian fishing village receives a mysterious guest: the Boto, who transforms into a human to seduce and be loved by women and hated by men. One of her conquests is the daughter of a fisherman, who has a son with the Boto. He constantly reappears to seduce her, and even when she marries, he continues to look for her. This provokes the ire of the husband, who wants to kill him anyway.
건축 기사인 빌 마캄은 아마존댐 건설 중 정글에서 일곱살난 아들 토미를 잃어버리고 고독한 탐색 작업을 한다. 10년간의 추적 끝에 토미의 실종이 인디오와 관계있음을 알게 된 그는 아마존을 탐색하다 어느 큰 폭포앞에 이르른다. 그 때 갑자기 기분 나쁜 소리가 들려오고 인디오들이 빌을 습격하기 시작하지만, 어디선가 날아온 화살이 그를 구한다.
