Likeable characters. And the lead characters are very likeable. Great acting, directing, casting. Plots all make sense .. albeit somewhat farfetched (but that's par for the course with just about every mystery series). And, ironically, although farfetched, some of the twists are predictable (others not). Calling this a 'mystery' series doesn't do it justice. Nor would calling it an 'investigative journalism' series. There are lots of family relationships covered as well. This is mostly a feel good kind of series. Unfortunately the episodes are all approx. 90 minutes, which is more than I like (but others might). I also feel that I know Italy a bit better having seen this series (and having actually been to Italy) - what with the cinematography, and dialogue.