After falsely accusing their nemesis, Dana Woletsky, of stealing Ashley's prom princess votes, Mary-Kate and Ashley set out to make it up to her by helping her win.
Mary-Kate becomes upset when her plan for her camp to win the summer contest with the camp down the road appears to be jeopardized by her twin sister Ashley's behavior.
Mary-Kate becomes jealous when the cool, older group at her school, the White Oak Academy for Girls, starts hanging out with her sister, Ashley, but they say she can be a part of their group, too, if she does something for them.
The twins' school trip to Florida starts off smashingly as Ashley is made captain of the triathlon team, but the adventure turns sour when Mary-Kate loses her diary and the dreaded Dana Woletsky shows up and tries to steal the loyalty of Ashley's team and the affection of her boyfriend.
Mary-Kate leaves White Oak Academy--and Ashley--after Ashley writes about her in the school gossip column, and the pair muddle through their separation by writing in their diaries; based on the real-life twins' television series.
