Here is the true tale of one of America's greatest missionaries, the French priest Father Jacques Marquette, who came by canoe from Canada with explorer Louis Joliet to convert the many Indian tribes and explore the "great river", which he named the Immaculate Conception. He braved the dangers of tomahawks and tortures to bring the Word of God to the Indians of the New World. Rapids, floods, Indian superstitions, tribal warfare - these are only a few of the innumberable obstacles Father Marquette and Louis Joliet encountered in their wild adventure.