In the late 19th century, a spirited young woman named Susan Bradley travels by train to the American West. She intends to marry a man she has corresponded with through letters. As she journeys, she befriends a group of women called the Harvey Girls, who are traveling to the same frontier town to work at a Harvey House restaurant. These restaurants are renowned establishments known for bringing a touch of civilization and good food to the rugged towns springing up alongside the expanding railroad. Upon arriving in Sandrock, Susan discovers that her fiancé is not what she had envisioned. Undeterred, she finds camaraderie and purpose among the Harvey Girls, joining them in their mission.

The new Harvey House draws the ire of the local saloon owner, Ned Trent, and his girlfriend Em, a saloon singer who sees the Harvey House as unwelcome competition threatening the saloon's dominance. Tensions rise between the saloon's rowdy patrons and the more refined standards introduced by the Harvey Girls. Meanwhile, Susan encounters various townsfolk including the charming but rough-edged Trent, who soon becomes a source of romantic tension. As Susan and the Harvey Girls work to establish their place in Sandrock, they face opposition but also find unexpected allies in their quest to bring a sense of order and refinement to the frontier town. With determination and spirit, they navigate through personal challenges and rivalries in their pursuit of happiness and community improvement.