Although 19-year-old Lloyd Dobler (John Cusack) is the main character of this film, the two story lines emanate from his love interest, Diane Court (Ione Skye). Their romance begins just after high school graduation. The relationship nourishes both of them, but Diane's doting father (John Mahoney) thinks directionless Lloyd isn't good enough for his high-achieving daughter. He's jealous of the time she spends with Lloyd, fearing Diane will give up her fellowship to stay near him. Bowing to pressure from her dad, Diane breaks up with Lloyd. As Lloyd endures his heartbreak, Diane learns that her father isn't the hero she thought. The story incorporates love and heartbreak, betrayal and the difficulty of forgiveness, and the emotional and physical separation between child and parent that's a necessary precursor to becoming a grown-up.