In the rugged 17th century Canadian wilderness, Father Laforgue, a young, idealistic Jesuit priest, is assigned to go up river into the wilderness on a perilous journey to convert the Huron Indians. His Algonquin Indian guides nickname him "Black Robe." His young aide and translator, Daniel, falls in love with Annuka, the beautiful daughter of the Algonquin chief. Torn between his own desires and ideals of the priesthood, Laforgue's faith is tested as the expedition faces the elements. Attacked, captured and brutalized by hostile Indians, the traumatic experience challenges everything the young priest believes. Together with his young companions, he escapes to complete his mission and comes to understand the true spirit of the land and the spirit he sought to convert.