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.
Место действия фильма — бразильские джунгли. Племя индейцев похищает пятилетнего мальчика, в то время как его отец, американский инженер, занят строительством дамбы. В течение десяти лет отец ищет сына, и после многочисленных приключений, полных экзотики, они встречаются в дебрях Амазонки.
