At a Florida campus, Professor Paul Delville and his wife Content, the Dean of Women, who have been happily married for sixteen years, lecture to their respective classes on matrimony. Both recount an experience from their own life as an illustration: One day, Paul and Content await the arrival of two houseguests--Paul's Swedish colleague, Professor Sveg and his daughter Katrin, whom they remember from their last meeting as a gawky teenager. Content, middle-aged and slightly insecure about her appearance, feels threatened when Katrin, who is now a statuesque blonde bombshell, appears and announces that her father has been delayed. After Content excuses herself to dress in preparation for a seminar that evening, Katrin informs the astounded Paul that she has chosen him to father her baby because of his brilliance. When Content enters the room, Paul tells her of Katrin's request, but she feigns amusement and leaves to attend the seminar. In reality, Katrin's declaration has rattled Content, and after her meeting, she turns to her friend Ross Barnett, a happily married language professor, for advice. At the Delville residence, meanwhile, Katrin presents Paul with a nude statue of herself that she has sculpted and then begins to "break down the barrier between them" by pulling a perfumed handkerchief from her bodice and handing it to Paul. As Katrin continues her dance of seduction, Paul hears the sound of Content's car roaring up the driveway and pulls away. Later that night, a sleepless Paul confesses to Content that Katrin threw herself at him and then reconfirms his love for his wife. To distract Katrin, Content asks the school's athletic director to invite them all to tea while the swim team is practicing. When Katrin appears clad in a fitted gold bathing suit, the boys leap out of the pool and flock around her, but she dismisses them as children. The next day, at the Delville house, Katrin lounges languidly in the sun with only a towel concealing her nakedness. Calling Katrin aside, Content scolds her for her behavior, to which Katrin protests that she does not want Paul, just his child. When Content warns her that Paul is off limits, Katrin blithely declares that that is Paul's choice to make. As the Delvilles anxiously await the arrival of Katrin's father, Katrin shows Paul a letter, written in Swedish by her father, stating that his work will prevent him from joining her. Content has gone to the market, and in her absence Katrin passionately kisses Paul. Feeling his resistance rapidly fading, Paul asks Katrin to leave. When Content returns from shopping, Paul tells her of his decision, but she chastises him for succumbing to Katrin's charms and suggests that he allow the girl to see his "true boring self." At Content's insistence, Paul invites Katrin to accompany him to a lecture that night. After Katrin and Paul leave, Content finds the letter and calls Ross to translate, arranging to meet him at the lecture hall. When Content arrives, however, she discovers that the lecture is scheduled for the following day and the hall is empty. After Ross translates Prof. Sveg's letter, Content is certain that Paul betrayed her. When Ross suggests making Paul jealous and starts to flirt with Content, she calls his bluff and asks Ross and his wife Marion to drive her to the airport so she can fly home to her mother in Brooklyn. Meanwhile, Katrin and Paul return home and find the empty envelope on the floor. Paul, concerned, asks Katrin not to tell Content about their failure to attend the lecture, and Katrin agrees on the condition that he kiss her. Just as they embrace, Content comes in and confronts Paul with the letter. After admitting that he took Katrin for a drive and a hamburger, Paul insists that the kiss was innocent. Furious, Content storms out of the house. Afterward, Paul observes that Katrin is really looking for a husband, and Katrin acknowledges that she is no longer interested in him as a biological mate. When Content returns to retrieve some papers, Katrin announces that she is leaving to find a man of her own. After she departs, Paul begs Content to stay, and after he declares that he greatly treasures their marriage, they reconcile.