After complaining about the dead metaphor (and dull generic familiarity) of serial killers elsewhere, let me say upfront: Roncaglio exploits the conventions and the premise to some unexpected effect. While his hapless, almost Chance-the-Gardeneresque prosecutor protagonist struggles to fill out the paperwork involved, the appearance of ritually burned/mutilated bodies gets him in dutch with the pervasively corrupt military higher-ups. There's some lovely stuff early on with the obsessive Chacaltana, whose blindered preoccupations with rules (and 'round women) help the author tease out a nightmarish vision of the Fujimori/Sendero-Luminoso era Peru.
But I found myself losing focus as I veered between the dreamlike intensity of its sociopolitical horrors and the (in this case too-)generic demands of a crime-thriller plot, and the graft didn't take, for this reader. Still, an ambitious undertaking, with a bleak black sense of humor.