Cullen awakens on a barren prairie to the sound of a piano. He stumbles, dry-heaving, to a pile of abandoned furniture. Ezra Dutson, disheveled, stands beside the piano pointing a knife at Cullen. Cullen asks for water. Ezra runs away. Cullen collapses.
Earlier that morning, Cullen sits on the balcony of his train car.
Ruth hands him a list with names of sick and deceased workers. Cullen sniffs his water jug then pours the water out.
Cullen pulls a dead rat from a water tank and orders all water tanks emptied. Cullen tells the workers, drought is sending rats and snakes into the tanks and cholera might be infecting the camp. The walking boss threatens to quit because Cullen is forcing them to "work without water in this heat, or die in the infirmary." The walking boss starts to draw his gun. Elam cold-cocks him from behind. Cullen fires the walking boss.
Cullen tells Elam he's going to Cheyenne to ask Durant for water, since the closest river is three days away.
In Cheyenne, Sen. Metcalf tells Durant, the government is auditing the state treasury soon and "the coffers need to be filled." Metcalf suggests cashing in Durant's Credit Mobilier stock.
In Durant's hotel room, Metcalf says Durant's railroad plan has failed. Metcalf grabs for the stock certificates and orders Durant to sign them over. Durant shoots him dead. Sean bursts into the room. Durant hands him his pistol and says, "What have you done?"
Later at the hotel, Cullen tries to broker a deal for water with Durant without success.
In Hell on Wheels, Sean asks Mickey for help. "How deep are you into it this time?" Mickey asks.
The heat wave and cholera epidemic continue. Ruth tells Eva to stay as far away as possible.
Eva finds Declan packing to leave. "Can't drink the whiskey or the water," he says. Eva says, she wants to go with him to New York because "the baby wouldn't make it here." She'll meet him on the last train out.
Cullen returns to Hell on Wheels as a group of railroad workers are leaving. One says, Cullen didn't bring the water he promised and a nearby Mormon fort has "water, food and wives to marry."
Feeling the early symptoms of cholera, Cullen rides out again in search of a spring ten miles away. He orders Elam to have the men build a windmill to pump the spring water.
Cullen's illness progresses. His horse leads him to a pond and drinks. Cullen finds a skull-and-crossbones sign indicating the water is poisoned. Cullen walks away from the pond on foot.
Elam and Psalms build the windmill. Psalms asks why Elam hasn't named his baby. "Every time I name something, somebody take it away from me," Elam replies, then says he wants to name her Rose.
Eva watches Elam hold the baby. He says he loves Eva "no matter what."
Back in Cheyenne, Sean shows Metcalf's corpse to Mickey who says the police will believe Durant, not Sean.
Mickey confronts a drunk Durant about the murder and offers to "make all your problems disappear." Mickey tells Durant not to run or call attention to himself.
Cullen wakes to pebbles being thrown at his head. Ezra stands nearby and points to a waterskin with his knife. Cullen offers jerky in return. Cullen asks where Ezra got the water.
Elam, Psalms and the freedmen throw bodies into a mass grave then set it afire. Sean and Mickey add Metcalf's corpse, wrapped in a blanket. Mickey says, "I never want to see you again in my life, Sean."
Durant cleans a bloodstain off his table.
Eva pricks her finger with a knife and draws the design of her own tattoo in blood on her baby's chin. She sings a Mojave prayer.
Cullen digs a hole that fills with water.
The Swede introduces himself as Bishop Dutson to an escort from the Mormon camp. The Swede says Indians killed his family.
Elam spots Cullen and Ezra beyond the pit of burning bodies. "Found it," yells Cullen.
Cullen wakes in the back of a cart to see the freedmen finishing the windmill. The pump works: The water runs clear. The men cheer. Psalms brings a bucket of fresh water to Cullen. "Fill them tanks," Cullen shouts.
In the church, Cullen asks Ruth what to do with Ezra. "Men say that luck's the only God left out here," Cullen tells Ezra. "Reckon you were my luck today." They play cards. Ruth smiles.
Eva hands the baby to Declan on the train. "You take good care of her now, Mr. Toole," she says. She's not going with them. Eva says the baby's name is Rose. Eva watches the train pull away.