Divorcee Doug Simpson is a radio station producer from California who lives with his two daughters, Katie and Bonnie. When his oldest daughter (Katie) turns 15, she suggests to her father that's it's time for her to start looking more grown-up. For the last 14 years, Katie had been wearing dowdy clothes, braces and thick glasses and hanging around with Richard, her next-door neighbor and long-time boyfriend (who had won Doug's approval); but when Doug leaves on a business trip, Katie transforms herself, along with the help of Doug's fiancée Janet Pearson, into a knockout beauty.

When Doug returns, he is shocked to find boys from every walk of life interested in dating Katie. Janet suggests that Doug needs psychiatric help when his obsession with Katie and her boyfriends reaches extreme limits. Throughout the latter half of the movie, Katie maintains three boyfriends, two of whom she eventually stops dating. At the end of the movie, Katie takes a class trip to Europe and reunites with Richard again — at which point Bonnie, her younger sister, begins her own dating spree.

Friends and Studio 60 on the Sunset Strip star Matthew Perry played Katie's third boyfriend, Timothy in this movie. He was credited as Matthew L. Perry.
Beach Boys member Brian Wilson performs the song "Daddy's Little Girl" on the movie's soundtrack.
Singer and American Idol judge Paula Abdul served as a choreographer for the film.