Stefano is a successful fifty-years-old, but disappointed and unmotivated. He works as editorial director for a publishing house and lives in the beautiful world of city fiction and intelligentsia, literary awards, cultured parties. He has a young but painstaking lover, Silvia, to whom he published her first novel. He has an older confidant, Renata, manager of the publishing house, and few friends working with him, Mara and Paolo. He is divorced from his wife, Sara, a wealthy woman who still allowed him to live in her family home, a messy house, left to go, full of books and manuscripts.
One morning, Stefano wakes up and discovers that there is a woman in his apartment, Sophie, with a French accent: Sara, who is currently on a cruise, sent her to look after him and the apartment.
After an initial resistance, Stefano lets himself be convinced. Sophie enters his life: she becomes the best of the housekeepers, the best of the cooks, the best of the secretaries. The house becomes clean like a mirror, books in order, tasty dishes.
The woman is mysterious: she listens to classical music, reads books, sometimes goes out in the evening elegantly dressed. Her image does not coincide with that of the waitress and this mysterious element fascinates Stefano, who seeks some answers by confiding in friends.
Everyone is amazed at Stefano's radical change, flourishing again in life, as "thawed" by a period of darkening. The love for Sophie subjugated him and brought him back to emotions; he can start new plans.
When everything seems to turn perfectly, here is the turning point: Sophie, who had already given some mysterious signal, disappears
Stefano doesn't understand it and doesn't accept it. He searches for Sophie at Sara's house, but there he discovers that his wife has never had on duty a woman named Sophie. Moreover the ex-wife had never gone on a cruise around the world but she is in her mountain house. Stefano, increasingly angry and disappointed, decides to reach Sara.
Sara reveals to Stefano that he was literally played: at a poker table. In fact, Sophie lost a huge sum playing against Sara and Sara offered her to cancel her debt in case she would had been successful in making Stefano fall in love, warming his "heart in winter". Sophie succeeded in achiving it: Stefano fell in love and was overwhelmed by a bet between women.
There would be every reason to go back to defeat to depression, but Stefano has a shot of male pride that leads him to the resolution of the story and the film.