Charles Exbrayat is one of the leading masters of the French detective genre. During his long literary career he wrote more than 160 novels, and their total circulation in France and abroad exceeded 20 million copies. Many of his novels were adapted for film and television. Possessing universally recognized literary talent, Exbrayat is considered the creator of a special genre — the humorous detective, where suspense and entertainment are combined with sparkling humor.
In the novel, the events unfold on soil native to the author. The town of Albi, the center of the historic Albigeois region, was known throughout the Christian world in the late 11th and early 12th centuries: the Albigensians, a branch of the heretical Cathar sect, had settled there, and to deal with them the Pope had to proclaim crusades against the Albigensians, which went down in history as the Albigensian Wars. At that time passions boiled around Albi; it stood at the center of a great political game. It was then that the papal legate Amalric uttered the famous phrase that enriched the cabinet of curiosities of rabid fanaticism: Kill them all, God will know His own. By the way, this formula — God will know His own — would be quite a fitting title for a detective story, and if instead of the Lord one substituted His eternal adversary, it would suit this Exbrayat novel as well.