A young boy, Rio, is forced to go on the run across the American Southwest in a desperate attempt to save his sister from his villainous uncle. Along the way, he encounters Sheriff Pat Garrett, on the hunt for the infamous outlaw Billy the Kid. Rio finds himself increasingly entwined in the lives of these two legendary figures as the cat-and-mouse game of Billy the Kid's final year of life plays out. Ultimately he is forced to choose which type of man he is going to become, the outlaw or the man of valor, and will use this self-realization in a final act to save his family.