In the second half of the 20th, century, a small circle of French noir writers began publishing a large number of novels, some of which were co-written. This was notably the case of Laissez bronzer les cadavres, co-signed in 1971 by the foremost French crime fiction author of his period, Jean-Patrick Manchette, and another figure of Gallimard's famous ‘‘Série Noire’’ collection and of the ‘‘neo-polar’’ world in general, Jean-Pierre Bastid. Using stylometry, we attempt to analyze this joint work to unveil the writing process and the dynamic of creation between the two writers. Our results show that if the text was indeed co-written by the two authors, Manchette very probably played a leading role in finalizing the novel.