When eleven-year-old Wesley loses her father in a car accident, she and her mother must move in with her Aunt Cindy, an Australian shepherd breeder in Prince Edward County, Ontario. Life on a working farm is new to Wesley and she is lonely, confused and angry at life's injustices as she struggles to fit in to this new world. After watching the birth of a litter of puppies with her cousin Cassel, Wesley pleads with her aunt to save the life of a runt puppy that would otherwise be left to die. The puppy, an undersized red merle named Piper, proves to be a challenge from the start, with a natural talent for trouble as well as herding sheep. When Piper attacks a sheep during a herding competition, Wesley must fight once again to prove the dog's worth, and ultimately, her own. Through hard work and long hours, the dog and girl become inseparable, and even stand a chance at the championship title. But on the eve of the big event, Piper and Wesley are set upon by marauding coydogs--coyotes crossed with wild dogs--and it is Piper who is called upon to save Wesley. Will the dog save the girl who gave her a second chance? Will they still have a chance at the big title?