Newly graduated from high school, Buzzy Pringle shocks his family by telling them that he has eloped with Rosemary Cotts, a high school junior. He explains that he will work at his father's business during the summer, and in the fall he will go to college and Rosemary will finish high school. Buzzy's parents, Jeff and Carol, accept the situation and offer the newlyweds a room in their house. Buzzy's sister, Elizabeth, however, is upset by the marriage of her younger brother because her own wedding, to Freddy, is only a few weeks away. Rosemary soon comes to feel that she is being treated like a baby, and she leaves to live with friends. Elizabeth and Freddy begin to quarrel, and Buzzy learns that his salary is being paid from his father's expense account. Carol blames all the troubles on Jeff, who is relegated to sleeping on the living-room couch until the problems are resolved. Buzzy finds a job at a gas line station and moves into an apartment with a forgiving Rosemary. Elizabeth and Freddy move up their wedding date, and Jeff and Carol are reconciled.