The original Broadway production starred Anthony Perkins and Mia Farrow as Jason Carmichael and Phoebe Craddock respectively.
Michael Caine was originally offered the stage role of playwright Jason Carmichael, but he insisted on the contract guaranteeing him the film role as well. The part went to Anthony Perkins. Caine had recently played a playwright in the movie 'Deathtrap' (1982).
The film was made and first released about four years after its source play of the same name by Bernard Slade was first staged in 1979.
The movie and source stage play's story were inspired by a quote Ernest Hemingway's real life scenario. He wrote: "I have been in love with a woman for forty years, but when she was married, I was single . . . and when I was married, she was single. We were victims of unsynchronized passion." A tagline for the movie actually stated: ''When he was married, she was single . . . and when she was married he was single. They were victims of unsynchronized passion.''