This series is about the retired police inspector Hannes König, concerned with murders in and around the lovely town of Bamberg, Oberfranken, Northern Bavaria. He is helping (or helped by) his successor, the young and all but conservative Axel Hübner. The cases are as realistic as you would expect from an above-average TV series, and this might be actually reason enough to like the story.
But the special charm of this series lies in the way how the peculiarities of Franconia (Franken) are depicted. It starts with the vineyard where König lives, continues with the distinct dialect of the coroner and various other characters, and culminates in an authentic presentation of the savoir-vivre in the area. I don't know any other series that represents Franconia in such an intriguing manner as this one.