While attending a New York musical with her Connecticut family, Leone Merrick, who has just turned nineteen, runs into her aunt, Winifred "Winkie" Lamont, and Winkie's lover, painter Max Lawrence, outside the theater. Struck by the worldy Max, Leone, who has just been told by her boyfriend, young Geoffry Cole, that she is too innocent and inexperienced for him, gushes in his presence and flatters his aging ego. Later, Winkie, in an attempt to revive her flagging affair, insists that Max and she spend the weekend at the Merricks' home and sends a telegram to Leone's mother Laura in Max's name. When the lonely but excitable Laura receives the telegram, she swoons at the thought of Max, a man she remembers as her first great love, coming to her home. Laura's aging, cranky husband Augustus, however, scorns her excitment and, when two-time divorcée Winkie arrives, overtly expresses his disapproval of her. Oblivious to her sister's involvement with Max, Laura confesses to Winkie that Max had once romanced her and had promised to "return for her" one day. When Max finally arrives, Laura flirts openly with him and is blind to his pointed lack of interest in her. Although Winkie pretends not to know Max, she is unmasked when Leone shows up and reveals to her parents that she had met the couple the previous night. Disgusted by Winkie's infidelity, Augustus orders Max to leave, but Leone begs him to ignore her father and stay. Flattered by Leone's childish but intense interest, Max agrees to stay and, after all but dismissing Winkie, meets the young woman in her life-sized doll house. Then, while surrounded by stuffed animals and dolls, Max confesses his love to Leone and begs her to marry him. After Leone eagerly accepts the proposal, Laura confides in a dejected Winkie her belief that Max and she are going to elope. Laura then corners Max, who admits that he is in love but assumes that Laura understands that Leone is the object of his affection. So in need of romance, however, Laura, who married the older Augustus as a young woman, misconstrues all of Max's words and prepares to tell her husband goodbye. When Augustus deduces the situation, he talks privately with Leone and begs her not to marry Max, but she dismisses his concerns. The next morning, Geoffry arrives at the house, determined to win Leone back, but is rebuffed repeatedly by her. During a family game of Twenty Questions, Leone reveals her engagement to Max, devastating not only Geoffry but Laura as well. That night, after Winkie chides Max for his weak ego and curses his engagement, Augustus counsels Geoffry to be more aggressive. Augustus then orders Laura to tell Leone about her own marital unhappiness and convince her of the folly of marrying an older man. In spite of Laura's frank words, Leone refuses to back down and prepares to leave with Max. As they are going out the door, however, Leone sees Geoffry stretched out on the ground, apparently unconscious, and screams with anguish. Leone's reaction to Geoffry's faked condition convinces Max that she truly loves the younger man, and when Laura finally confronts Max with their supposed romantic past, he decides to leave quietly with Winkie. Later, Laura confesses to Augustus that Max had been her first love, but Augustus correctly recalls that the man that she had loved as a young woman was actually a pianist named Lawrence Mack.