 Horse trainer Shawn O Hara and his lovely niece, Margaret, come to America to escape the memory of an accident involving Margaret s brother, Danny. Working with thoroughbreds in Kentucky, Shawn takes a liking to a yearling named Seabiscuit, and fights to convince the horse s owner that the tiny horse with big knees will become a top-notch racehorse. Meanwhile, Margaret begins a tentative relationship with jockey Ted Knowles, but is haunted by her brother s death in a steeplechase spill.