In a flashback, a young Elam wins his master a bet by reading aloud from the Bible. Elam’s master's friends worry about slaves learning to read, but he maintains, "It's like a parrot recitin' Shakespeare."
Later, with his fellow slaves, Elam recites a biblical passage describing God's promise to deliver the Israelites from slavery.
In the Pullman with his top men, Durant expresses confidence in the future but confides to The Swede that financial troubles remain. Durant plans to escort Lily to Chicago and meet with Crane to resolve them. The Swede suggests that Lily is fond of Durant.
On the railroad platform, Lily reminisces to Cullen about the life in America she and Robert had envisioned. As Lily steps onto the train to leave, Eva rushes over and begs Cullen to save Elam. The Swede is permitting the Irish to hang Elam to "let off some steam."
At the saloon, the Irish draw guns when the freedmen arrive to rescue Elam, but Elam sends the freedmen away because, he says, it's pointless for them to die, too. The freedmen leave after Elam secures Toole's guarantee that they won't be harmed.
Toole describes the Irish to Elam as the "n***ers of the British Empire" and admits that he's hanging Elam to prove that his countrymen aren't the lowest in America, too.
After Elam is strung up, Cullen charges in on horseback and shoots the man holding the rope. Elam drops to the floor, and Cullen instructs him to ride off on one of the horses outside. Cullen cautions the Irish against pursuing them, then joins Elam galloping away.
The Swede blames Toole for creating a mess and stabs his face with a fork for refusing to pursue Cullen. Bolan suggests that he and Dix would have better luck leading the men anyway.
Cullen and Elam stop far away from town, where Cullen scolds Elam for sleeping with a white woman. "I'm a free man," says Elam. Not that free, replies Cullen.
By a campfire that night, Elam asks rhetorically what would happen if he owned a white woman, had a son by her, and educated the boy just enough that he considered himself different from his fellow white slaves. Reflecting on his own life, Elam concludes that in truth the boy wouldn't be different at all.
En route to Chicago and drunk on brandy, Durant describes for Lily the time when as an impoverished child he earned a penny by eating a rotten apple to amuse two rich gentlemen. The humiliation spurred Durant's future success, though he fears that he may not survive his current predicament. "Get your head out of that bottle and figure out a way," chides Lily.
Back at the campfire, Cullen recalls freeing his slaves to please his wife, realizing only later that she was right to make him do so. Following her murder, his barn was set afire. The slave woman who raised Cullen died inside the barn trying to shield his son from the flames.
The next morning, Cullen teaches Elam to shoot a gun. Elam's shots miss the target, but Cullen explains that the "trick" is counting rounds and making sure that his opponent has to reload his weapon first.
In the Pullman, Durant tells Lily that he's figured a way out of his dilemma. The Union Pacific needs a connecting route back to New York, and the two options are the M&M Railroad and the R&R. Durant predicts Crane would do anything for a stock tip about Durant's choice.
Durant delivers Lily to Robert's family's Chicago home for what turns out to be a memorial gathering. Robert's sister Charlotte, wearing black, comments that Lily, dressed in red, must have already stopped mourning.
Durant heads to Crane's office. The senator demands the stock tip outright and threatens Durant with prison for remaining silent. "It's the R&R," Durant blurts. "Put everything you have into it."
Meanwhile, Lily overhears Charlotte gossiping that Robert would still be alive if he hadn't tried to save Lily. When Lily says that she, not Robert killed their attacker, Charlotte calls her a liar. Lily slaps Charlotte and describes ripping the arrow from her shoulder and thrusting it through the Indian's throat.
Durant returns just in time to hear Lily's account. When she finishes, he escorts her away.
Bolan and Dix lead the posse chasing Cullen and Elam. Bolan discovers warm dung and stands to warn the others about the ambush but gets shot in the chest. Cullen shoots two more men, and Elam a third, but Toole slips into the woods.
Toole and Elam fire at each other until Toole maneuvers himself in front of Elam, gun drawn. Smiling, Elam says that Toole's gun is empty and then shoots him in the mouth.
Durant purchases the M&M instead of the R&R and visits Crane's office to gloat over the senator's financial ruin. The deal netted Durant $5 million, allowing him to replace the $147,000 missing from the Union Pacific till. On his way out the door, Durant flips Crane a penny.
Lily joins Durant on the train back to Hell on Wheels, saying that she refuses to return to London and a life she now despises. Durant stuns Lily by courting her. "If I had you by my side," he says, "there is nothing I, we, couldn't do together."
Back in the woods, standing among the bodies, Cullen finds a Bible and wonders if he should read a passage over the dead men. Elam suggests the 23rd Psalm ("The Lord is my shepherd"). The two men recite it together, Elam from memory.