Socially awkward Muriel Heslop wants nothing more than to get married. Unfortunately, due to her oppressive politician father, Muriel has never even been on a date. Ostracized by her more socially adept friends, Muriel runs into fellow outcast Rhonda Epinstalk, and the two move from their small Australian town to the big city of Sydney, where Muriel changes her name and begins the arduous task of redesigning her life to match her fantasies.

Television show host Brett and his laid-back science journalist girlfriend Tash despair that they will ever truly understand each other. On their first anniversary, under a full moon, a frustrated Tash declares her wish that they could swap lives. The next morning, Brett and Tash awaken to find Tash's wish has come true. Forced to confront the unfamiliar sensations of their "new" bodies, both must navigate strange new experiences with friends and co-workers.

A young ambulance driver befriends an elderly woman.