At a Swiss spa, upper-class expatriate American Frederick Winterbourne (Barry Brown) meets pretty, nouveau riche flirt Daisy Miller (Cybill Shepherd); her bratty, xenophobic little brother Randolph (James McMurtry); and her tremulous, nattering mother (Cloris Leachman). Despite warnings from his dowager aunt (Mildred Natwick) about Daisy's recklessness with men, Winterbourne finds himself drawn to her. When he encounters her again in Rome, he tries to convince her that her liberated behavior with an Italian admirer (Duilio Del Prete) may sully her reputation in aristocratic circles. But Winterbourne cannot reconcile his feelings for Daisy with the manners that he is used to following, nor can he fathom how she may feel about him beneath her veneer of willful coquetry. After society matron Mrs. Walker (Eileen Brennan) ostracizes her, Daisy's final rash action reveals to Winterbourne how his old-fashioned mores may have sealed her fate.