A female doctor gets obsessed with the case of a dead woman after learning that the woman had died shortly after having rung her door for help.

Paris, 1920s. Marguerite Dumont is a wealthy woman, lover of the music and the opera. She loves to sing for her friends, although she's not a good singer. Both her friends and her husband have kept her fantasy. The problem begins when she decides to perform in front of a real audience.