Identical twins Sharon McKendrick and Susan Evers make each other's acquaintance at summer camp, not realizing at first that they are indeed sisters. At first rivals, pulling pranks on each other, their mischief ruins the camp dance. Their punishment is to live together in an isolated cabin where they bond. After both admitted they have come from broken homes, they soon learn that their parents Maggie and Mitch divorced shortly after the twins' birth, with each parent having custody of one daughter. The sisters, each dying to meet the parent they never knew, switch places in order to visit the parent they have never seen. While Susan is in Boston masquerading as Sharon, Sharon is in California masquerading as Susan.