The Doctor of Death: Marcel Petiot and the Dark Heart of Occupied Paris During the Nazi occupation of France, Dr. Marcel Petiot transformed his Parisian townhouse into a charnel house, murdering dozens—possibly more than a hundred—desperate refugees who believed he was helping them escape to freedom. This meticulously researched account traces Petiot's evolution from a troubled child exhibiting early warning signs of psychopathy through his career as a corrupt small-town physician to his emergence as one of history's most prolific serial killers. The book examines how the chaos of wartime France created perfect hunting conditions for a predator who understood that institutional collapse makes vulnerable populations easy prey. Through detailed analysis of his 1946 trial, the work explores how Petiot cynically appropriated the language of resistance to disguise systematic murder, how he exploited Jewish refugees fleeing the Holocaust, and how his case forced France to confront uncomfortable truths about collaboration, persecution, and moral ambiguity during the occupation years. This is both a riveting true crime narrative and a sobering examination of how societal breakdown enables atrocity, offering lessons that remain urgently relevant for understanding how predators exploit crisis and why institutional protections matter most when they seem most difficult to maintain.