"All Night Long" (1981) stars:
* Gene Hackman as George, a washed-up American singer
* Barbra Streisand as Cathy, a British woman who falls for George
* Paul Newman as a record producer
* Diana Sands as George's wife
* John Gielgud as Cathy's father
* Keith Carradine as a young musician
If you have a different film in mind, please provide more details like the year, genre, or any other actors you remember.