Fact1: Identical twins and Sharon McKendrick meet at Miss Inch 's Summer Camp for Girls, Fact2: Susan is at grandparents house pretending to be Sharon, Fact3: Sharon goes to father 's house pretending to be Susan, Fact4: Maggie and Susan fly to California, Fact5: Vicky was not used to climbing mountains and being in woods
Output: Identical twins Susan Evers and Sharon McKendrick Hayley Mills meet at Miss Inchs Summer Camp for Girls, unaware that they are sisters. Their identical appearance initially creates rivalry, and they pull pranks on each other, culminating in the camp dance being ruined. As punishment, Miss Inch decides that they must live together in the isolated Serendipity cabin and eat together at an Isolation Table for the remainder of the camp season. After discovering that they both come from single parent homes, they soon realize they are twin sisters and that their parents, Mitchell Mitch Evers Brian Keith and Margaret Maggie McKendrick Maureen OHara, divorced shortly after their birth, with each parent having custody of one of them. The twins, each eager to meet the parent she never knew, decide to switch places. Susan gives Sharon a matching haircut and has her bite her nails. They also take a crashcourse getting to know each other while learning about each others personalities and ways of life. While Susan is in Boston at their grandparents house pretending to be Sharon, Sharon goes to California to their fathers house, pretending to be Susan. Sharon learns their father is engaged to a childhating gold digger named Vicky Robinson Joanna Barnes. Sharon calls Susan to tell her that their father is planning to marry Vicky, who is beautiful and dangerous, and that she must bring their mother to California immediately. Susan eventually reveals to their mother and grandparents the truth about their switching places. They are extremely happy to see Susan again, and Maggie and Susan fly to California. After Mitch and Maggie are reunited, they argue and the twins make their surprise appearance together. Mitch is extremely happy to see Sharon again, and after he tells Vicky the truth about the twins, she is shocked and furious — especially after learning that Maggie plans to spend the night at his house. The girls recreate their parents first date at the Italian restaurant Martinellis with a gypsy violinist. The former spouses are gradually drawn together, but have another fight with Maggie telling Mitch that she and Sharon are leaving in the morning, and that she wishes him the best of everything with Vicky. Susan and Sharon try to find a way to delay their return to Boston, so the twins dress and talk alike so their parents are unable to tell them apart. They will reveal who is who only after returning from the annual family camping trip. Mitch and Maggie reluctantly agree. Vicky is furious, so Maggie tricks her into taking her place and letting her know it would give her a chance to get to know the twins better. Mitch was an outdoorsman, but Vicky was not, and she was not used to climbing mountains and being in the woods, so the twins decide to play tricks on her. Vicky spends her time swatting mosquitoes after unknowingly using sugared water instead of mosquito repellent, and being awakened by two bear cubs licking honey off her feet, which the twins had previously placed there. Vicky finally throws a screaming tantrum and screams at Hecky, the ranch foreman, to take her home. After breaking a fishing pole, knocking down the food table and throwing food, she pushes Mitch, with a face full of shaving cream, into the tent. The twins give Vicky the clothes she borrowed from Mitch, and Vicky slaps one of them in the face. Mitch finally sees the truth about Vicky, and after she and Hecky leave, Mitch and the twins return home. Back at the house, the twins apologize for what they did to Vicky, and are forgiven. Maggie makes dinner, and Mitch talks about what their life was like when they were married. They realized they still loved each other, and did not want to grow into a couple of old and lonely people. They share a kiss, and decide to remarry. The twins, their grandparents, and Hecky and Verbena the housekeeper, are present at their wedding, with the Reverend Dr. Mosby conducting the ceremony.