Convict Umberto is allowed to work outside prison during daytime as a librarian. There he falls for a beautiful woman who mistakes him for a volunteer helping the inmates — however, like a modern-day Cinderella, every day he must leave and be back to his cell before midnight... will they manage to live happily ever after?

Giuseppe Moscati, Doctor saint of Naples, was a doctor of the early twentieth century, from an aristocratic family devoted his career to serving the poor. The film focuses on the human side, partially leaving aside the spiritual part.