Content Warning: The source material includes descriptions of murder. It also utilizes offensive stereotypes of Indigenous Americans and frequently refers to characters by their ethnicity. These terms are replicated in the guide only in direct quotes from the source material.

In October 1914, three brothers, Alfred, Tristan, and Samuel leave their father's ranch in Montana to ride north to Calgary and enlist to fight in World War I. They are accompanied by One Stab, their father’s closest friend. Alfred is the eldest brother, Tristan the middle, and Samuel the youngest. Along the way, they stop at a roadside tavern, but the owner refuses to let One Stab enter. Tristan beats the man then pays for liquor and beer, and they picnic outside. They arrive in Calgary and are trained for a month in Quebec, where their positions in the army are fixed: Alfred is an officer, Tristan a horse wrangler, and Samuel an aide-de-camp.

Back at the Montana ranch, their father, Ludlow, becomes sick while he waits for One Stab to return with news of his sons. He writes letters to his wife, Isabel, who spends winters in Boston. She asked Ludlow to keep Samuel out of the war and left early for Boston when he did not.