Since 2008, the Fourniret affair has been devastating France and Belgium. The serial killer Michel Fourniret was sentenced to life imprisonment for a series of kidnappings, rapes and murders. His wife, Monique Olivier, was also given life imprisonment with preventive detention of twenty-eight years. Their shadows continue to hover over some thirty unsolved murders.

In 2014, the journalist Oli Porri Santoro began his investigation; and in the process, he met and befriended Selim, the only son of the diabolical couple. Selim had since built a new life for himself in the south of France, under a new identity.

The day after their meeting, fate intervened. Selim received a letter from his father, whom he had not heard from for ten years. Over the next ten years, Santoro and Selim began corresponding with Fourniret (there are more than a hundred letters) and met him in prison at Ensisheim in Alsace.

This is a true story never before told, with unpublished confessions of murders never obtained by investigators, the revealing of the name of a potential accomplice, evidence of Michel Fourniret's presence at the Ranucci trial in 1976, and the truth about the fate of the remains of the Postiches gang treasure.