It's the day of the senior prom at Herbert Hoover High School. The prom has been organized by the one of the most popular girls at the school, the beautiful but obnoxious Patrice Johnson. When Shelley Sheridan and her jock boyfriend Kevin McCrea break up just before the prom because she refuses to sleep with him, they are both forced to try to find new dates at short notice. When Shelley can't find a new date, she lies to her friends and tells them that she is going to a college frat party instead. In fact she goes to the town cinema to watch an old horror movie, where she assumes that she will not run into anyone from school. But she bumps into Dan Lefcourt, one of the school geeks, who has also gone to the cinema to avoid the prom. Dan has lied to his father, telling him that he was going to the prom because he didn't want his father to find out that he has a low social status at school and couldn't get a date. Dan helps Shelley avoid being seen by another group of students, and she soon discovers that he is a really nice guy. After one of Kevin's friends tells him a false story about an unpopular girl at the school, Angela Strull, being "easy", Kevin decides to invite her to the prom. Angela is delighted to be going to the prom with Kevin. Her friend Margaret is initially supportive, but later becomes sceptical of Kevin's motives. Not only does Kevin have to try hoodwink Margaret into believing that his intentions are honorable, he also has to contend with Angela's overprotective, religious fanatic pharmacist father, Ed, who tries to follow the two "lovebirds" all night, eventually getting arrested for his trouble. Meanwhile, Patrice is confident that she'll be named the prom queen when her only real competition, Shelley, doesn't show up at the prom. To that end, she's arranged for an all-night celebration with her boyfriend Roger, who she keeps on a short string. But then Angela appears in Cinderella fashion, and Angela and Kevin are voted prom queen and king. Kevin tries to get Angela into bed, but she resists and confronts him about his real reasons for asking her out. When he explains that he really does like her now, she points out that he should have respected her from the start. By the end of the film, at Hudson's aka Hud's Angela has learned that her parents had to get married because they conceived her while they were high school students; confident after her night as prom queen, she informs them she's going to art school in Italy rather than Bible college. Kevin ends his night without sex and defends Angela's honor when his friend makes a lewd comment. Meanwhile, Shelley and Dan announce that they are now going steady, much to the shock of every senior in the room.
