The official introduction says that each Le Carnet d’Oscar volume contains a complete investigation. A continuing thread also develops between books. Your starting point depends on how you want to follow that continuity.
The four listed volumes in order
- L’Homme au visage d’eau.
- Le Mur vide.
- Les Eaux de la Vesdre.
- Le Silence des Fagnes.
Choose your first read
Start with book one to meet the characters gradually. For a standalone case, read a volume’s introduction and choose what attracts you. Avoid detailed summaries of the other books beforehand.
FAQ
Are the previous books compulsory?
The site says the investigations stand alone; sequence preserves the continuing thread.
Is there a fifth volume?
On 19 October 2026, the official page lists it as being written, without a publication date.
Sources and further reading
The book
The Empty Wall is the second book of Oscar’s Notebook, a series of crime novels set in Liège.
