What if you spent your whole life wishing for something you didn't know you already had? Halllie Parker and Annie James are about to find out. Hallie is a cool girl from California. Annie is a fair rose from London. When the two accidentally meet at a summer camp, they think they have nothing in common except they're identical twins (Lindsay Lohan). Now they're up to their freckles in schemes and dreams to switch places, get their parents (Dennis Quaid and Natasha Richardson) back together and have the family they've wished for!