Bohannon tries to find himself again while continuing to drive the westward expansion of the Union Pacific Railroad, under Durant's leadership. Bohannon takes up with a gang of train robbers, but is turned over to the Union Army and imprisoned. Durant manages to get him pardoned. The railroad construction enters the Sioux territory, where the Swede and a misguided Reverend Cole assist the natives in attacking the railroad. Lily Bell seeks to gain control of the railroad from Durant and mails his accounting ledgers to the government. Army officers arrive to find the town has been attacked by the Sioux. Bohannon helps protect the town, while the Swede strangles Lily to death.