The Virginian, Betsy and Judge Garth meet the train at Medicine Bow and greet Big Jim Lafferty (Leo Gordon), the foreman, and a crew of Chinese coolies whom the Judge has hired to clear a way through the pass. The crew is observed arriving by Colton and Junius Antlow's son, Chris (Tom Simcox). Rafferty decides to dig a tunnel through a granite outcrop and believes there is plenty of time to do so before winter comes and the cattle starve. The Virginian posts Randy and other Shiloh hands as guards along the mountain ridge as he believes Junius will try and sabotage the operation. The Chinese workers start making the tunnel. Amongst them is a very slight individual whom the Virginian suspects is a woman in disguise. Junius Antlow gets Colton to sabotage the dynamite being used to blast the tunnel. When the workers set off a blast the explosion is much greater than anticipated and two workers are killed. The slight Chinese is also injured but is rescued by the Virginian who is himself injured in the process and the two are taken to Shiloh where they are treated by Dr. Spaulding (John Bryant). The Chinese (Cely Carrillo) is revealed as a woman who speaks English, whose name is Kam Ho, and who was raised by Chang (Kam Tong) one of the other workers. While recovering, Kam Ho becomes good friends with the Virginian and Betsy.
Lafferty and the Judge suspect sabotage in the explosion but have no proof. The Virginian takes Kam Ho to town to visit the doctor and while in the restaurant they meet Chris Antlow. The Virginian tells him of the explosion and hints it might be sabotage. Chris returns and confronts his father who admits he is reponsible and Chris tells him he has committed murder. At Shiloh it is clear Kam Ho is falling for the Virginian. She reveals she was pledged by her parents to marry Chang whom she does not love. Frustrated in further attempts at sabotage, Junius Antlow, who lived in the Orient, instructs Colton to cut the pigtail off a Chinese worker as this will demoralize the workers who believe loss of the hair would remove their souls. Colton manages to sneak up on Chang and cut off his pigtail which has some of the desired effect but Lafferty convinces the rest of the Chinese to keep working as he will protect them and they do manage to break the tunnel through. A desperate Junius decides to attack the tunnel with all his men and blow it up with dynamite and he pushes his wife out of the way when she tries to stop him. After he leaves, Chris Antlow arrives, learns what has taken place from his mother and rides to warn the Judge at the tunnel. The Judge tells Chris that he had been forced to shoot Junius in self-defence when he confronted his father driving out some homesteaders ten years before.
Antlow and his men arrive at the tunnel and are confronted by Chris Antlow who gets killed by Colton who in turn is killed by the Virginian. With the death of his son Junius is inconsolable and loses interest in the tunnel. Meanwhile, the Virginian discovers Kam Ho trying to kill herself and stops her. She reveals her love for the Virginian and that she can not marry Chang, so she sees suicide as the only honourable way out. However, the Virginian tells her she would dishonour him with her suicide – because he saved her life in the tunnel explosion, her life belongs to him so she can not destroy it. The only honourable solution is to deal honestly with Chang and the two Chinese are seen together as the episode ends.