David Palmer, a young chemist, returns to his father's Indiana farm, to marry a local school teacher, Ruth Treadwell. David meets again his father's horse-trainer, Ben Lathrop, whose daughter, Cissy, has left high school to help her father. Palmer marries and becomes wealthy through an invention, and is able to indulge his socially-ambitious wife. His father dies and Palmer returns to Indiana, where his interest in harness-racing is rekindled, as is his interest in Cissy Lathrop.
Chemist David Palmer comes back to his hometown in Indiana to get married to his girlfriend Ruth, a schoolteacher. He finds his father excited about the harness racing potential of a new mare that he's just traded for. When the mare is injured while winning her first race, David's father uses her for breeding, and she has a colt named Dan Patch, who proves exceptionally fast. Meanwhile, Ruth becomes increasingly frustrated with David's continued interest in horses, and with his friendship with his father's trainer and the trainer's daughter.
Story of the legendary trotting horse Dan Patch.