Hidden History and Secrets

The book explores the idea of a centuries-old secret—the Hollow Needle—that links French kings, the Man in the Iron Mask, and Arsène Lupin, revealing how hidden historical knowledge can empower those who possess it.

The château's past as an abbey and the mysterious circumstances of the crime hint at undisclosed secrets.

The cryptic document found at the scene and the mystery of the stolen items' replacement suggest hidden truths.

Beautrelet uncovers the secret crypt beneath the chapel, revealing Lupin's hidden lair and the true extent of the theft.

The kidnapping of Beautrelet's father and the deliberate suppression of Gaffer Charel's memory highlight the hidden truths and secrets that Lupin manipulates.