Kidnapped from his safe California home. Thrown into a life-and-death struggle on the frozen Arctic wilderness. Half St. Bernard, half shepherd, Buck learns many hard lessons as a sled dog: the lesson of the leash, of the cold, of near-starvation and cruelty. And the greatest lesson he learns from his last owner, John Thornton: the power of love and loyalty. Yet always, even at the side of the human he loves, Buck feels the pull in his bones, an urge to answer his wolf ancestors as they howl to him.