Successful PR pro Marni (Kristen Bell) heads home for her older brother's (Jimmy Wolk) wedding and discovers that he's marrying her high school arch nemesis (Odette Yustman), who's conveniently forgotten their problematic past. Then the bride's jet-setting aunt (Sigourney Weaver) bursts in and Marni's not-so-jet-setting mom (Jamie Lee Curtis) comes face to face with her own high school rival. The claws come out and old wounds are opened in this crazy comedy that proves that not all rivalries are forever.