1865. Katharina goes to a ball in Moscow. There she meets again Tchaikowsky, her first and only love. The young, who is now married to wealthy Michael Iwanowitsch Murakin, a man she does not love, has not forgotten Piotr Illich, the (not yet) famous composer. Both are still in love with each other but Piotr is engaged to Nastassia, a dancer, while for her part Katharina cannot leave her husband. Tchaikowky's first love then decides to sacrifice her happiness to the success of the composer, sponsoring him in secret. Something Piotr will learn only years after. When Katharina finds herself free at last it is too late: Tchaikowsky is dying of cholera and she only has time to close his eyes.
The French ballet girl Janine, a gifted tap-dancer, dreams of a musical career in Paris. But first she wants to take revenge on Count René who stood up her best friend Charlotte. Janine wants him to fall in love with her and disappoint him afterwards. At a masked ball at which Janine pretends to be a Marquise they have their first meeting. Janine is very disappointed in the "good gentleman", but she does not suspect that this gentleman also makes a pretence. The man whom she holds to be count René is Pierre, a composer and pianist.