The other DrC and I watch the PBS long-form British import Midsomer Murders, now in its 20-something TV season. It's slow pace often puts the other DrC to sleep, although she insists she likes it. I'd not call it my "favorite" but in TV's wasteland, it is well-crafted and not boring.
Midsomer Murders caters to the British nostalgia for village life, the setting is semi-rural and it largely avoids the "weekend party in the great house" beloved by British mystery authors. Lords and Ladies are mostly off-camera, the characters range from working class to upper middle class.
There is one theme that recurs time and again. It deals with the various secrets of parentage; illegitimacy, unfaithfulness, adoption, inheritance, etc. It must be an obsession of the British, of the people writing the series screenplays, or both.
In this program the plot device has reached the status of cliche. We find ourselves wondering which version of the old chestnut they'll drag out this week, and we're seldom disappointed.