A seasoned frontier trapper investigating an attacked emigrant train discovers two young captive settlers forced to perform for a band of Pawnee Loups and mounts a covert rescue. The episodic narrative traces horseback chases, rifle and lasso confrontations, captures and escapes, and instances of betrayal and unexpected accusation that complicate loyalties. Characters face moral and physical dangers on open riverbanks and plains, and the action culminates in a decisive confrontation that resolves the immediate threats while examining themes of survival, vengeance, and rough frontier justice.