The two things that are most striking about this film are its unqualified realism and the beauty of its wilderness photography.

The story takes place in the 17th century in what was to be Canada; it concerns a Jesuit priest (Father Laforgue) from an upper class family in France who comes to Quebec City and is tasked with traveling through the wilderness some 1,500 miles west to work at the Huron Mission there. Laforgue is accompanied on his journey by a party of Algonquin Indians as well as by Daniel, a young French interpreter who is primarily just up for the adventure.

As the journey proceeds and the seasons move from fall into a harsh winter the mood of the film becomes ever more bleak. The continuing culture clashes between the Algonqins and Laforgue are sometimes humorous but are ultimately sad in their revealing insights into how difficult it is for one culture to understand another. One scene has Laforgue transcribing a brief story told by the Algonquin chief and then having Daniel take the transcription some distance and read it back to another tribesman. Laforgue is trying to show the Indians that he has much to teach them, but their interpretation of the incident is that he must be some sort of demon. When the party meets up with some members of another tribe and they see Laforgue dressed in his black robe and ask if he is intelligent, the Algonquin chief quickly answers, "No." On the other hand Laforgue views the Indians in their current unenlightened state as savages.

Not all is love and harmony between the various Indian tribes. When the Lafourgue party encounters a band of Iroquois there are some scenes of violence and torture where the squeamish may want to avert their eyes.

Daniel, speaking the Algonquin language and having taken up with the chief's daughter, begins to have some understanding of the Indians and their ways. One interesting exchange between Daniel and Lagorgue is:

Daniel: They believe that in the forest at night the dead can see.

Laforgue: It's childish Daniel.

Daniel: Is it harder to believe than in men of paradise where we all sit on clouds and look at God?

Laforgue's most singular personal characteristic is his unwavering faith. His reaction to sexual temptation is confession of sin and self flogging. He sincerely believes that Christianity can bring salvation to the Indians, but the Indians have their own gods and view Laforgue with incomprehension. The film's success in making us understand both of these positions gives the ultimate conclusion a dimension of tragedy.