Life is good for Buck in Santa Clara Valley, where he spends his days eating and sleeping in the golden sunshine. But, one day, a treacherous act of betrayal leads to his kidnap, and he is forced into a life of toil and danger. Dragged away to be a sledge dog in the harsh and freezing cold Yukon, Buck must fight for his survival. Can he rise above his enemies and become the master of his realm once again?