Kidnapped from his California home and sold to prospectors embarked for the Yukon Gold Rush, Buck, a pampered house dog who has known comfort all of his life, finds himself thrust into a brutal world of cruel human masters, savage fellow sled-dogs, and an unforgiving wilderness full of hardship and misery. In the wilds, Buck earns the love of a man as rugged as he is, and he reacquaints himself with his true animal nature, a noble heritage passed...