At some point, it came into the possession of one of the Heads of Hogwarts School of Witchcraft and Wizardry, and has since been kept in the Headmaster's study. A long line of successive headmasters and headmistresses of the school have presumably attempted to unlock its secrets, however, if any of them succeeded, its content might have proven either too mundane or too potentially dangerous for them to choose to divulge it, seen as the subject of the book is a mystery, with all that is known about it being it is handwritten in an unfamiliar runic alphabet.
Behind the scenes
- This book is only mentioned as a possible answer to a hypothetical question posed during the sorting quiz on Pottermore. Therefore, it is unclear if this book does actually exist in historical canon.
- Since it is kept in the Headmaster's office and never moved to the library, it could very well be that its content might have proven too potentially dangerous in the wrong hand to be accessible to the students at all, even if kept in the Restricted Section, seen as Dumbledore himself removed the books about Horcruxes from the library to his office for that reason.
- Pottermore (First appearance)