In pre-WWI Chicago, Illinois, a factory worker named Bill fights with the foreman and accidentally kills the man, provoking him to leave town with his young sister, Linda, and his girlfriend, Abby. Arriving by train in Texas, they are hired as farm hands in the wheat fields of a wealthy, young famer who is single and has no family. Bill and Abby claim that they are brother and sister to avoid gossip. While Linda makes a new friend, Abby catches the eye of the young farmer who instructs his foreman to find out more about her. Meanwhile, Bill gets into a fight with another farm hand who insinuates that Bill and his “sister” have an incestuous relationship. Sometime later, Bill sneaks to the famer’s house to find some salve for Abby’s injured hand, and overhears a conversation between the young man and his doctor. The farmer has a terminal illness and could die within a year. On another day, the farmer asks Abby where she will go once the harvest is over and she admits that she is not sure. At the end of the season, the farmer asks Abby to stay and to continue to work for him. When Abby tells Bill, he encourages her to remain and charm the farmer into marrying her so she can inherit his fortune. Abby is appalled by the suggestion but eventually agrees on the condition that Bill and Linda, her supposed “brother and sister,” stay on as well. Linda bids a tearful farewell to her friend as the other farm workers leave. In time, Abby marries the farmer and Bill and Linda move into the house with them. Abby, Bill and Linda enjoy their new life; however, the farmer notices that Bill and Abby are unusually affectionate siblings. As Bill and Abby sneak off in the middle of the night, the foreman warns the farmer that Bill and Abby are hustlers, but the farmer refuses to believe him and sends him away. As the foreman leaves, he tells Bill that he is aware of the "sibling's" scheme. Time passes and Bill becomes frustrated when the farmer does not die as expected. A travelling circus’ airplane lands on the farm; and the performers and crew are invited to stay for a while. One night, as Bill and Abby party with the new guests, the farmer sees Bill give Abby a short kiss on the lips. The farmer wakes Abby in the middle of the night and demands to know what is going on between her and Bill. Although Abby insists that they are just affectionate siblings, she later tells Bill that she feels guilty for hurting the farmer. Realizing that Abby has fallen in love, Bill leaves town but returns at the beginning of the next harvest. Abby and Linda are happy to see him; and Bill and Abby privately apologize to each other. As they bid each other farewell, the farmer watches from his rooftop and becomes enraged when they kiss. Later that day, locusts plague the farmland and the workers struggle to smoke them out with a bonfire throughout the night. Bill stays on to help, but the farmer challenges him to a fight, which results in overturned lanterns that ignite an uncontrollable fire. The entire harvest burns. Bill finds Abby and tells her that the farmer knows their secret and insists that they run away. As Abby packs to go, the farmer catches her. He pulls out a gun, ties her up, and goes after Bill. The farmer searches all night and finds Bill at dawn. As the farmer raises his gun, Bill stabs him in the chest with a screwdriver and runs away. As the foreman finds the farmer dying, Bill, Abby and Linda escape. After pawning jewelry, they buy a boat and travel down the river, living off the land, but Abby is wracked with guilt. The foreman and the local police track them down. When Bill sees the police coming, he grabs his shotgun and runs; however, the police give chase and shoot him dead, leaving Abby and Linda devastated. Months later, Abby puts Linda in a boarding school and hops on a train filled with soldiers heading to war. Linda’s old friend from the farm finds her in the school and helps her run away. Reunited, the friends wander aimlessly down the train tracks.