On January 9, 1993, Jean-Claude Romand killed his wife, his children, his parents, and then tried to commit suicide. The investigation of this crime revealed that he was not a doctor as he had claimed for eighteen years… Emmanuel Carrère’s decision to write about this life of lies in his best-seller ‘’The Adversary’’ was a perilous and painful experience. But it gave rise to a unique style blending the excellence of nonfiction genre and the novelist’s obsessive quest to understand the killer’s mindset.