I have yet to find a decent South Korean television series either on netflix (my blog) or elsewhere, i just don’t get into them. Films are different take:
imdb: tt6302160 is a rather hysterical worst case scenario of a Nuclear incident. It has some merit although a little ill-informed concentrating on what ifs rather than reality.
I am sure there good kdramas but kung fu doctors and mermaids all seem to suffer from extremely pretty actors rather than characters with shiny glasses and fish tanks which Japan has a lot of and are a meme.
North Korean stuff will get its own post which is more documentary than fiction at some future point.
So i am probably the wrong person to ask.