A journey into madness that makes us empathize with the unforgivable.

One day, journalist Alexandre Kauffmann interviews a murderous psychopath who has spent forty years locked up in various French “units for difficult patients”. In one of these closed and little-known places, the murderer tells him that he has encountered “the most dangerous man” he has ever met. Alexandre Kauffmann sets out to find this dangerous man. A titanic quest which, for two years, will take him into judicial archives, a boxing gym and several prisons. His “target” always seems to elude him until the journalist learns that this man might soon be released… A face-to-face meeting becomes possible. A difficult question arises: when do we decide to release a man who has committed acts that society deems reprehensible? Alexandre Kauffmann wants to understand this man and why doctors, certain relatives and a judge are convinced that he has changed.

The first narrative thread is that of the journalist’s quest. Alexandre Kauffmann manages to gain access to several units for difficult patients, where he meets prisoners like “Crocodile”, a child killer, “Blue Helmet”, a man equipped with a foam helmet because he distributes headbutts to patients who approach him, and “Rocaille”, a Scrabble player who thinks that Alexandre Kauffmann works for The Daily Planet.

The second narrative thread of the book immerses us in the legal, penitentiary and psychiatric journey of its subject, the mysterious “dangerous man”. A journey that interrogates our institutions as much as it does humankind: “He admits to having killed his mother, to having mutilated her and to having thrown her leg out of the window in order to attract the attention of the police.”