Oppressed by her husband, her lover, and her obsessive mother, a bourgeois woman is reunited with a childhood companion at the central train station in Milan. Throughout 24 hours there, she will experience her particular descent into hell.

Who is the mysterious stranger Cecilia met on the street? Why is he suspicious of everyone? She is happily married, has a lovely child and a good job: yet she decides to join him and to become his lover, sharing his destiny right up to its tragic conclusion.