Cullen Bohannon finds himself a stranger in a strange land: Truckee, California. Home to the headquarters of the Central Pacific railroad, this rough mountain railroad town teems with thousands of Chinese workers who are foreign in language, culture and traditions. While grappling with the challenges of corralling his new workforce, Cullen leads the Central Pacific’s herculean effort to tunnel through the Sierra Nevada mountains, sometimes achieving only inches a day in the race to complete America’s first Transcontinental Railroad.
Cullen is in California with the Central Pacific Railroad, and must deal with the new workers.
Cullen and Fong find themselves in peril as they transport a locomotive over the Sierra Nevada mountains. The Swede gains Phineas' trust.
Cullen contends with violence in Chinatown set off by disgruntled railroad workers. Meanwhile, the Swede manipulates Phineas in his plot against the Mormons.
Cullen solves a Chinese labor strike in the wake of violence. Meanwhile, Durant pulls Mickey deeper into Union Pacific business.
Unexpected violence erupts in Chinatown during the festival of Tin Hau Don; Cullen confronts the Swede; and Durant involves Maggie in his latest scheme.
Cullen and Mei escort precious cargo through the California wilderness; Eva nurses Louise back to health.
Cullen and Durant meet with President Grant to discuss the future of the railroad; the Swede puts his plan against the Mormons in action.
The Swede's murderous rampage on the Hatch homestead results in a long overdue showdown with Cullen.
Cullen faces life-changing decisions in Utah as Truckee adapts to life without him.
Cullen's nitroglycerin experiment provides an explosive backdrop for the railroad life in Truckee. Durant's plan turns deadly.
Durant's plot to ransom himself takes an unexpected turn when Campbell arrives in town with the Cavalry to coordinate a rescue operation.
Chang force Mei to leave Truckee after discovering her secret; Cullen exorcises some old demons during his search.
The race to finish the railroad comes down to inches, forcing all parties to contemplate the end of the line, and what the future holds for them.