I’m not going to C&P from Wikipedia. However, I’m going to suggest that you look up what the PBS series Mystery was showing in the 1980s & early 90s. They did British mystery & detective shows before everyone could just rent stuff on video, and there was no longer a market for such a show.
IIRC, The first Prime Suspect series was shown on Mystery, and so were subsequent ones, albeit, the last, or possibly last two, may have been shown as stand-alone series.
Which, BTW, I am seconding ALL the* Prime Suspect *series. They are each about six episodes, and, again, IIRC, there are five series, at 1 hour per episode.
I believe the Agatha Christie series were part of Mystery back in the 80s as well. Almost everything was very, very good.
Look at the list of what was shown on Mystery, then check them out on IMDb, and see what appeals to you.
I don’t know how old you are. I’m assuming you are in the US, so it very likely you have seen long before the Covid-19 shut-down, the show Law & Order (the original series). But if you are young, or not in the US, and for some reason have missed this show, watch it. It’s my favorite US drama ever.
If you are in the US, and have not seen the UK version of Law & Order, it’s worth watching the UK version. If you are a fan of the US version, and have watched the episodes more than once, you will recognize them in the UK versions, but in many cases the endings have changed, and in a few, the object lesson has changed, because in that specific case, UK values are very different. It’s an interesting process. And it keep you on the edge, once you realize that nothing is predictable, just because basic plots were borrowed.
Again, I don’t know where you are, or your age, but if you have not seen David Lynch’s Twin Peaks, it’s a must-watch for anyone who likes suspense with just a little bit of supernatural overtone. It premiered with a 2-hr. TV-movie, so make sure you watch this first. Don’t start with what is called “episode one.” That is the first 1-hr episode in its regular time slot, and assumes you have seen the 2-hr movie. I watched this just about 18 months ago (and I saw it in its original run). It really holds up.
Also, unless you hate black & white with a passion, as some people irrationally do, in between your series, you might catch up on Alfred Hitchcock movies you have not seen, as well as some of the other classic suspense films you may not have seen. Two excellent ones are Witness for the Prosecution (1957), and Murder on the Orient Express (1974)-- NOT the 2017 version NOT, NOT NOT!
Have fun!