We get a double dose of Hayley Mills in this Disney vehicle: she plays 13-year-old identical twins Susan and Sharon, who meet for the very first time in summer camp. They soon learn that they were separated at a very early age when their parents Mitch and Maggie (Brian Keith and Maureen O'Hara) divorced. On a lark, the girls switch places: the one living with Mitch goes back home with Maggie, and vice versa. Mitch is planning to remarry the "wrong woman," vituperative Vicky (Joanna Barnes). The twins conspire to reunite their parents, but the road to reconciliation is rough indeed. It takes a slapsticky camping trip to get rid of the troublesome Vicky and to prompt Mitch and Maggie to renew their vows. The film introduced a hit song, "Let's Get Together," which represented the high point of Hayley Mills' very short-lived recording career. The Parent Trap was based on Das Doppelte Lottchen, a novel by Erich Kastner, which had previously been filmed in German and British versions (real twins were cast in both); over thirty years after Parent Trap was theatrically released, a short series of sequels were made for the Disney Channel cable service, with a grown-up Mills back in her original role(s), and two sets of second-generation twins. Baby Boom collaborators Nancy Meyers and Charles Shyer would remake the film with a new cast in 1998.
~ Hal Erickson, All Movie Guide