Perhaps if this wasn't the first Marshal Guarnaccia book I read, I'd compare it to others Magdalen Nabb has written (a dozen, so far). But as a first-time reader, I kept thinking about Simenon's Inspector Maigret, and so, using that as a template: The scenic environs--Florence here, rather than Paris; Italy, not France--provide a similar kind of pleasure; a trip abroad to a different culture. And with similarly intense protagonists. The reader can feel confident that no matter the mystery, both the Chief Inspector and the Marshal, with their dedication to duty and their native acuity, will inevitably solve the crime.
But the Marshal is a notch above those he can dispatch within the Pitti station (despite the authoritative capped M), and is lower on the police pecking order than the Lieutenant, the Magistrate, and other capped officials in the Italian police bureaucracy. Unlike Inspector Maigret, in his roost at Quai des Orfevres (headquarters, not a mere police station), there's a self-effacing quality to the Marshal. In fact, he's in Florence from the south (earning money to send home), and so the reader gets a taste of the Italian north-south dichotomy. It's thus fitting that unlike Maigret, he is not supremely self-confident, but rather, self-effacing, often doubting his own abilities.
The writing is good, with a smooth flow from description to dialogue, from recollected past to physical present. And both authors present, through their protagonists, a keen observation of details. What for me most separates Simenon and Nabb--though admittedly I'm contrasting this one book to the dozens of Maigrets I've read--is the intricacy of the mysteries themselves. Simenon is less interested in the unraveling than in his characters, and though this leads to an occasionally flaccid story, it gives him more leeway for psychological exploration. Nabb sticks closer to the objective details, and dwells less on motive. I Think, Therefore Who Am I?