Twenty years have passed since the theft of the 'Code Noir', a significant historical book that was stolen during renovations at the Château des Ducs de Bretagne in Nantes in January 2006. This case has puzzled investigators as it marks one of the rare instances of cultural property theft within the castle grounds. Despite various efforts by local police, the whereabouts of the book remain a mystery, and the case is categorized as a cold case.

The theft is particularly notable not for the value of the item taken, which was not one of the castle's prized possessions, but rather for its implications regarding the security of cultural heritage within historical sites. The stolen book, while lesser-known compared to other artifacts housed in the castle like the tapestries or Turner’s watercolor, has nonetheless captivated attention due to the lack of clarity surrounding the criminal actions taken during the renovation period. Given that this incident has not been resolved yet, it raises concerns about the protection mechanisms in place for valuable cultural items.

As the anniversary of the theft passes, the local police continue to seek any leads that could shed light on the case, which has become emblematic of broader issues related to art crime and the challenges of recovering stolen cultural heritage. The ongoing mystery of the 'Code Noir' theft serves as a reminder of the vulnerabilities faced by institutions that house historically significant items, and the story continues to intrigue both locals and historians alike.