In 1942 Nazi-occupied Paris, a young and impoverished accompanist named Sophie Vasseur gets a job with famed singer Irene Brice. As Irene's possessive husband and manager, Charles, a businessman collaborating with the Nazis, wrestles with his conscience, the highly impressionable Sophie becomes obsessed with Irene, taking on the role of maid as well as accompanist, living life vicariously through Irene's triumphs and affairs, especially romantic. When Irene relocates to London, Sophie goes along, much to the discomfort of Charles.