Two young people open fire on passengers in a train, spreading terror and fear. At the same time, one of Lovecraft’s fans is dealing in human skin, and people all over France begin committing terrible murders. But behind all this madness lies a malicious will, and Ludivine Vanker, an investigator in the Paris department, must uncover the mystery of this ominous conspiracy. In the world of Maxime Chattam, evil is never alone—it is always part of an elaborate and terrifying plan hatched by predators. Who stands behind these murders? In the second part of the cycle "Paris Investigation Department," it seems as if the devil himself is pulling the strings.