I love Endeavour. We’ve seen all the Lewises and Moses except for the last Morse. Couldn’t watch that one. If you can find Campion, Cadfael, Unforgotten, those all are excellent, too.
All good ones.
A favorite oldie is Bergerac.
Cadfael is on this list: https://www.ranker.com/list/best-british-detective-series/ranker-tv
I love going through to pick ones I’ve never heard of. “Shetland” is good but its VERY intense.