Marcus Didus Falco is a private informer plying his trade in the slums of the Aventine hill neighborhood of Rome during the period roughly from the time of Nero to the time of Domitian. He is also on the imperial payroll to quietly check up on what the bureaucracy is up to from the time of Vespasian onward. This causes him a bit of angst, as he is not fond of the principiate, but with 12 cohorts of the Praetorian guard to enforce the emperor's will, there is not a whole lot he or anyone else who has a problem with the concept can do about it. The books work just a bit better as anthropological studies and history than they do as mysteries or suspense stories, but as studies about how folks lived and worked in the days before the empire began its precipitous slide they make really fun reading. One of the books is set in Pompei in 75, and you have a sort of sad compassion for the folks as they struggle along doing their best while really horrible forces under them get ready to belch forth and consume them. Same author (Lindsy Davis) wrote a romance based on the English Civil war which has the same problem. Great anthropology, interesting history from an interesting perspective, but as a romance novel, meh. If you are into suspense novels just for the plots, this is a good series to miss. If you are into history and interesting life stories and anthropological imaginings, this stuff is great.