Arriving at from Dawson for the second time, only thirty days after they had departed, the dogs are . Along with the others, Buck has lost a lot of weight. The men immediately received new orders, and were told to sell of their and replace them with fresh ones.
Two men from the States, Hal and buy the dogs and the sled very cheaply. Neither man looks like he belongs, nor does Mercedes, wife of Charles, sister of Hal. Buck watches as they clumsily take down the camp, improperly rolling the , and loading up the sled unevenly. The team cannot move the sled. They are repeatedly whipped by , as Mercedes cries over them.
When the sled finally moves, it falls on its side. Finally taking the advice of those around them, they remove many of the unnecessary items, though cries over them, and more dogs are added to the team. The journey begins, and the new dogs are relatively useless.
They are barely traveling ten miles a day and they soon run short on dog . One by one dogs are . The first dog to die is , and then all the new dogs die. The men and Mercedes are constantly arguing with one another.
Mercedes begins to ride on the . Mercedes refuses to walk even when the men lift her off the sled and drop her in the . Eventually the dog food runs out completely, and Hal feeds the dogs strips of frozen . Buck’s fur is covered with from the wounds Hal has inflicted with his club. The other dogs are equally badly off.
One day falls and cannot get up. Hal kills him with an and cuts him out of the traces. The next day dies, but the five remaining struggle on, despite their serious pains. They all stagger into Thornton’s camp for a rest. John warns the travelers that the ice is , and the trail is likely to drop out at any moment. Hal refuses to listen, and begins to the dogs to make them rise. But remains on the ground and he refuses to move. Hal takes up the club, but Buck will not move. He is too numb.
Suddenly John springs upon Hal and tells him that he will him if he hits the dog one more time. John cuts Buck's traces, and the rest of the team leaves. A quarter of a away, the breaks and the sled goes down, taking humans and dogs with it.