The narrative opens on the Pacific coast, where the Shawanoe hero Deerfoot, the Blackfoot youth Mul-tal-la, and the twin brothers George and Victor Shelton gaze upon the vast ocean before turning their canoes eastward. Their journey up the Columbia River is fraught with freezing temperatures, dangerous rapids, and the strict moral tests imposed by Deerfoot's unwavering principles. Upon reaching the Nez Perce village, they discover that Chief Amokeat has appropriated Deerfoot's matchless stallion, Whirlwind, for a hostile expedition. When Amokeat returns after a disastrous conflict with wandering Assiniboines, he confesses that the prized steed has fallen into enemy hands.
Determined to recover his horse, Deerfoot embarks on a lone tracking mission through the rugged, snow-dusted peaks of the Rocky Mountains, outwitting hostile bands and surviving grueling physical trials. Along the way, he encounters a strange dwarf who provides a healing herbal remedy for a severely sprained ankle, enabling him to continue his quest. Eventually locating the Assiniboine camp, Deerfoot stealthily infiltrates the enemy lines, slays a sentinel in a fierce knife duel, and recovers Whirlwind in a dramatic midnight escape. After rejoining his white companions, the party presses onward through the mountain passes, eventually arriving safely in the extensive Blackfoot territory. There, amidst tribal tensions and cultural divides, Deerfoot demonstrates his extraordinary athletic and moral superiority, ultimately leading the proud Blackfoot war chief Taggarak and many of his people to embrace the Christian faith.
