I received an ARC compliments of SOHO.
Magdalen Nabb constructed a plausible scenario - characters, motivations, wherewith all - to fit the facts of a true unsolved serial killer's murders around Florence from 1968 to 1985.That's only part of it. She uses the murders as the basis for an investigation that is driven by ambition rather than a search for the truth, until Marshal Guarnaccia becomes unsettled over the discrepancies of the case. This makes for a richly layered plot that at times is as confusing and frustrating to the reader as it is to the Marshal. It's also quite enjoyable despite the fact that the subject matter is grim.
This was my first encounter with Marshal Gaurnaccia which may not have been as satisfying as beginning with one of the first books of the series, but I'll be getting around to them I'm sure.