Patricia and Isobelle O'Sullivan arrive at St. Claire, an all‑female college, to study and settle into a new home. There they meet Alison, Wella, Catherine, and Doris, who also live at St. Claire, and the girls quickly bond over a shared sense of team spirit. Together they play games and enjoy many fun moments, living in harmony until Winfred appears, a sulky, rude, and antisocial girl who creates trouble for the O'Sullivan twins and their friends.