Jean-Luc must find her, the capricious unknown woman. She writes the most seductive letters in the world. And she has captured his heart. Jean-Luc Champollion - known to all his friends as 'Jean-Duc' - is what the French call an homme à femmes. With the ladies, the charming gallery owner has an easy time. And if it were up to him, life alongside his faithful Dalmatian dog Cézanne could continue just like this. But a letter that Jean-Luc pulls from his mailbox one morning sends him into a whole new orbit. 'To the Duc' is written on the envelope, which is inscribed in pale blue ink. It is a love letter, without a doubt. An exceedingly enchanting love letter, even. But who wrote it? And why does the author use a language that seems to belong to the nineteenth century, signing off majestically as 'The Principessa'?.