After securing needed supplies, the group travels by canoe along the river and gains a new companion, Shasta, a young Pah Utah. Shasta helps them with hunting, fishing, and river craft, while the boys face the search for food, night voyages, drifting, pursuit, and threats from wild animals. The river journey becomes more than travel; it tests their survival skills, judgment, and trust in one another. After many dangers, Shasta leaves the party with humor and courage behind him, and his departure becomes a turning point in the boys’ growth and the tone of the adventure.