Three curious and mischievous siblings-nine-year-old Kirk, eight-year-old Chelsea, and six-year-old Samantha-are ready for a whole new set of adventures First, the whole family leaves their home in Washington to take a vacation to Southern California. They stop to visit an old Spanish mission, where the children stumble on a surprising secret. Then the family travels to Switzerland for Dad's work. While on an outing, Samantha seems to disappear...