Buck, a large and handsome dog who is part St. Bernard and part Scotch sheep dog, lives on a sizable estate in California’s Santa Clara Valley. He is four years old and was born on the estate, which is owned by the wealthy Judge Miller. Buck is the undisputed master of Judge Miller’s place, as the locals call it, and is beloved by the Miller children and grandchildren. Buck has the run of the entire place, confident of his superiority to the pampered house pets and the fox terriers that live in the kennels.