On Durant's return trip from Chicago to Hell on Wheels, Indians sabotage the tracks, derailing the train ahead of his. Durant and Lily attend to the many wounded victims.
When The Swede arrives on the scene, Durant orders him to have Cullen lead a response force and learns that Cullen and Elam have been run out of town after the hanging incident. "You were going to hang a Negro for screwing a whore?" Durant criticizes, irritated.
Moments later, Cullen and Elam appear on horseback. The Swede and Cullen both pull guns, but Cullen draws faster. The Swede pleads for mercy. Cullen uncocks his gun but then smashes The Swede's face with it and whips him with a leather strap until Lily and Durant intervene.
At Hell on Wheels, the church tent becomes a makeshift hospital. The carnage shocks Ruth, and Reverend Cole moans that all is lost. "Blood is God here," he declares, before fainting.
In the Pullman, Durant orders Cullen and Lieutenant Griggs, the lead U.S. cavalry officer, to track down the Indian attackers. Griggs balks at teaming up with an ex-Confederate but relents after Durant threatens to contact Griggs's commanding general. Joseph will accompany the mission to lead them to the Cheyenne camp and negotiate with Chief Many Horses.
Alone with Cullen, Durant calls Griggs a hothead. They can't risk him starting a war, but the attacks must cease. Kill the renegade Indians, instructs Durant.
Outside the Pullman, Cullen teases Lily for taking up with Durant. "I am not a kept woman," she responds, offended.
Outside the cathouse, Cullen asks Elam to join the Indian mission because Cullen doesn't trust the Union soldiers not to take revenge on a Confederate.
Elam shows Eva his gun and tells her he's off to fight the Indians. "I don't want no dead man's trade," she says, before admitting how much she feared for his life after the hanging and subsequent posse attack.
Dressed in Indian garb and armed with arrows, Joseph tells Ruth that he must find Pawnee Killer before he starts a war. Joseph hands Ruth his hat.
Joseph, Elam, and Cullen meet up with Griggs, who sneers that his eight-man contingent includes an "Indian, a ni**er, and a Greyback."
Lily informs Durant that she's moving out of his train car and onto Hell on Wheels, using the tent she and Robert shared. "You played me like a fiddle," responds Durant, who spitefully denies her Henri’s help in removing her belongings.
In Cheyenne country, Joseph tells Griggs that Chief Many Horses will know where Pawnee Killer is. Alone with Joseph, Elam questions the reliability of Griggs's pledge not to harm the women and children.
Cullen notices the Confederate saber on Griggs's belt. "Spoils of victory" from the Battle of Antietam, boasts Griggs.
Two men pitch Lily's tent near the cathouse. Eva advises Lily to hire a carpenter to lay floorboards to avoid getting trench foot.
Around the campfire, Griggs laughingly describes the Confederate retreat at Antietam. It only happened, counters Cullen, because his side ran out of ammunition after killing so many Yankees.
"We won, and you lost," taunts Griggs, and he has the sword to prove it. Cullen moves to forcefully take the sword from Griggs, but Elam restrains him.
The next morning, the men awake to the screams of one of the Union soldiers and discover him hanging, mutilated, from a tree nearby. Griggs blames the incident on Chief Many Horses, but Joseph says it's the work of Pawnee Killer.
While the men are in the woods, the Cheyenne steal their horses. Cullen advises a return to Hell on Wheels, but Griggs insists on marching toward the Indian village anyway.
Cullen tells Elam that if the villagers don't escape before Griggs arrives, there will likely be bloodshed and the two of them may have to battle the Union soldiers.
In the church tent, Ruth tends to Reverend Cole, who sits in bed staring at a bottle of whiskey. Ruth calls him a drunkard and recalls childhood memories of him beating her mother. Cole moves to slap her but stops short. "I am not my mother," challenges Ruth. "I'm not afraid of you."
Cullen realizes that Joseph is misdirecting the group to buy time so the Cheyenne villagers can escape. Joseph admits it's true but vows that once his family is safe he'll track down Pawnee Killer.
After hearing an Indian call, two soldiers begin firing, but Cullen warns them to stop.
With Lily, at the outdoor mess kitchen, Eva reveals that Indians killed her family but spared her because she had smallpox. After she recovered, they sold her to another tribe.
Lily describes her nightmares about the Indian she killed. His spirit wants to drag Lily into the dead world, Eva explains. "When a woman kills a brave, it invites big magic."
Durant visits The Swede's quarters to say that, barring another Indian attack, railroad work should resume. The Swede, preoccupied with papers spread over his floor, says he can prove that Cullen is a killer. Durant doesn't care. Half the men in camp are killers, and Cullen is an “agent of progress," he argues.
In her tent, Lily struggles in the mud to install floorboards. Outside, Durant calls to her. When she doesn't respond, he ties Robert's pocket watch to her tent.
Griggs's party comes upon a recently evacuated Indian encampment. Griggs accuses Joseph of plotting with his brother. A young brave appears, and Griggs shoots him dead. As Cullen, Elam, and Joseph aim weapons at Griggs, an arrow pierces his shoulder, and a large Cheyenne war party begins to attack.