After making love to a beautiful Indian woman in the jungles of Brazil, a young Catholic priest returning to his mission is killed by a water snake. She raises their child, a boy, near the place where the river runs black. After he sees his mother murdered by white men in search of gold the jungle boy is adopted by two freshwater dolphins.

Years later, the young priest's superior Father O'Reilly (Charle Durning), finds the child, takes him to the city, and renames him Lazaro. Despite his love for the boy, he enrolls him in a covenant school. Lazaro rebels against the restrictive rules and regulations of civilization, and when by chance he sees the man who murdered his mother, his primitive instincts re-emerge: Lazaro becomes obsessed with revenge.

Christopher Cain (The Stone Boy) has crafted a remarkable film based upon David Kendall's novel Lazaro. Young Alessandro Rabelo is superb as the jungle boy. Similar in many ways to John Boorman's The Emerald Forest, Where the River Runs Black offers much food for thought on the clash between Indian and white cultures, the low tolerance of organized religion for other lifestyles, and the gentle and caring bonds which can be established between dolphins and human beings. The melodic and enchanting musical score by James Horner enhances the drama and the poignancy of this very special movie.