Freaky Friday is a 1976 American fantasy-comedy film directed by Gary Nelson, with the screenplay written by Mary Rodgers based on her 1972 novel of the same name. The film stars Barbara Harris and Jodie Foster in the lead roles. John Astin, Patsy Kelly, Dick Van Patten, Sorrell Booke and Charlene Tilton are featured in supporting roles. In the film, a mother and her daughter switch their bodies, and they get a taste of each other's lives. The cause of the switch is left unexplained in this film, but occurs on Friday the 13th, when Ellen and Annabel, in different places, say about each other at the same time, "I wish I could switch places with her for just one day". Rodgers added a water skiing subplot to her screenplay.