Serena and her grandfather, Henry, visit an old home near St. Louis which has special meaning for them. The home had once been a farm at the time of the Civil War and some of their ancestors had been slaves there. Henry tells Serena the story of a slave named Thomas, their ancestor, and his friendship with Nathan Reneau, the farm owner's son.Thomas and Nathan become best friends as young boys and spend most days together playing and riding their ponies...