Paris, 1979 - 1980. Pascal resolutely delays getting his philosophy thesis underway. Christine, his girlfriend, can't understand his casual attitude. Sarah is a singer in a baroque trio and dedicates herself to her art. Manuel, her boyfriend, tries to support her. The trio conceive future projects together, in particular an event based around Monteverdi. Directed by the Innommable, the trio's musician, a man as cruel as he is arrogant, Sarah devotes herself body and soul to the recording of "Lamento dela Ninfa."
The disc is released and achieves a considerable success. Christine gives it to Pascal for Christmas; he discovers and is delighted by Sarah's voice. Sarah continues her work sessions with the Innommable, but he is increasingly humiliating and violent. She finally gives up.
Pascal progressively sinks into a torpor and melancholy and can no longer stand being with Christine. She leaves him. Both marked in the same way by misfortune, intimately linked by music, Sarah and Pascal lose themselves in a shared dream. But how long will it last?