Set on the American prairie in the late 19th century, the story follows widower Jacob Witting and his two children, Anna and Caleb, who still grieve the loss of their mother. Longing for companionship and stability, Jacob places an ad for a mail-order bride. Sarah Elisabeth Wheaton, a practical and self-reliant woman from Maine, responds.
 
She arrives wearing a yellow bonnet and gradually brings warmth and possibility back into their lives. Anna and Caleb teach her prairie ways; in return, Sarah shares stories of the sea and helps rebuild the family’s sense of unity. Though the children worry she might return to the coast, Sarah ultimately decides that the pull of family is stronger. By the end, Jacob and Sarah are married, and the family looks forward to a hopeful future together.