Sad little rich girl Alyssa (Ashley Olsen) and orphaned tomboy Amanda (Mary-Kate Olsen) meet at summer camp and discover that they are each other's exact double. And each girl is worried about her caregiver. Alyssa's father, Roger (Steve Guttenberg), is about to marry a gold digger, and Amanda's kind social worker, Diane (Kirstie Alley), will be pushed aside if a cruel family adopts Amanda. The girls decide to switch identities to make their loved ones fall in love with each other.