A soldier returns home from World War I with a beautiful black horse that he saved on the battlefield, and names Thunderhoof. He enters the horse in a local race, hoping to earn enough money to save the family ranch of the girl he loves. However, the crooks intent on taking the ranch manage to capture a notorious wild horse and enter it in the same race, believing that it can beat Thunderhoof and thereby ensure that they're able to take the ranch.

Hugh Allan
as Bill Moran

Rex
as Thunderhoof, a horse

June Marlowe
as Helen Cunningham

Scott Seaton
as Colonel Cunningham

Hayes E. Robertson
as Washington - stableman

William Bailey
as Jim Kennedy

Jack Pratt
as Davis

Valerie
as Valerie - a horse