This is the first book I Bourgoin hands. The author does not cite its sources, we are therefore obliged to trust him on the content. First rub. Second problem: the book is presented as a collection of examples that are not necessarily put in touch (more in the chapter on American serial killers, all the same, to be the highlight of the author). It reads well as a novel, but Stéphane Bourgoin often share in long digressions in force, can gradually lose the thread of the story took place. As for the killers of the Belle Epoque, Bourgoin reproduced whole passages from a 1919 book, The Painted Criminals themselves Raymond Hesse. Strangely indeed, crimes that took place during the Restoration (Antoine Léger) or the Second Empire (Dumollard, the killer good) are classified in the "Killers of the Belle Epoque" (strictly speaking, covers the period basically the years 1880-1914 in France). And that's where the rub: Stéphane Bourgoin simply, in this book, to align the detailed examples but almost without any comments, thus in the chapter on French killers. An approach that is accessible to everyone, if one has the sources from which he draws his examples here. Moreover, we appreciate the sometimes look almost "naturalistic", you would think of Zola fired, in the words of Raymond Hesse. In that chapter, the purpose is therefore limited to a collection of extracts from a source or nearly devoid of critical apparatus.
In short, a collection of exempla, in the Latin sense of the word, certainly entertaining, but did not learn much, I think, to the understanding of serial killers (except in the chapter on American male killers, by far the over worked, but as Bourgoin does not cite its sources, impossible to check even if one feels reading this is his specialty). We must therefore acquire if one wishes to have the facts about some well-documented cases, but not for anything else.