Set in contemporary Paris, the movie is a variation of the classic Greek myth of Orpheus. At the Café des Poètes, a brawl is staged by acolytes of the Princess (Casares) and the young poet Cègeste (Edouard Dermithe), a rival of Orpheus, is killed. Cègeste's body is taken to the Princess's car by her associates, and Orpheus (Marais) is asked to accompany them as a witness. They drive to a chateau (the landscape through the car windows are presented in negative) accompanied by abstract poetry on the radio. This takes the form of seemingly meaningless messages, like those broadcast to the French Resistance from London during the Occupation.
Orpheus becomes obsessed with Death (the Princess). Heurtebise (Périer), her chauffeur, entertains analogous unrequited love for Orpheus's wife Eurydice (Marie Déa). They fall in love. Eurydice is killed by the Princess's henchmen and Orpheus goes after her into the Underworld. Although they have become dangerously entangled, the Princess sends Orpheus back out of the Underworld, to carry on his life with Eurydice, but he cannot look at her or she will die. (This diverges from the common classical account found in the Roman versions of the myth by Ovid and Virgil, where Eurydice is lost forever.) They believe it to have been a dream, Eurydice is revealed to be alive, and expecting a child.
Source : Wikipedia