Young Johnny's disappointment in leaving Pennsylvania for the wilds of an Idaho ranch gradually fades as his attention is captured by the beautiful Appaloosa, Chief, acquired from an Indian neighbor. But the affection is not mutual, for on his first ride, Johnny is thrown by the spirited pony. As he learns to keep a ""firm hand on the rein"" he also gains wisdom on a more symbolic level. Instead of running from the rattler poised to attack his father, Johnny manages to kill the creature. When father gambles sister Marg's education fund and the family's dwindling bank account on the town race, Johnny takes over and wins the final event. Colorful background material spiced with regional dialogue adds zest and charm to a boys' tale of the challenges and responsibilities of growing up in the not-so-old west.