Valeria is the young assistant of a film producer. She lives in an apartment on the same floor of her mother and writes anonymously for a successful screenplayer, Alessandro Pes. One day she bumps into an odd retired policeman who tells her a criminal story. Valeria is wary but listens fascinated by him. When she goes back home she uses the story she has heard from the man as the subject for the forthcoming script of Alessandro Pes, which has been expected to be consigned to the producers for a long time. The subject is appreciated to the extent that the movie is financed even by foreign companies and an old but well-known American director is employed to direct it. However, this is a dangerous subject. In fact, The stolen Caravaggio tells the mysterious theft of a famous painting by Caravaggio, La natività, which has been stolen in Palermo by the Mafia. As a consequence, Valeria will play a role which is unusual to her.
