Glad someone mentioned Deadwood, fantastic and I was really glad they did not just drag it out like so many good TV programmes, the film years later was good but not much as the TV programme.
The Shield also, for its time it was really shocking but excellent entertainment if you can call it that.
Six feet under, dark humour, loved it.
The Americans started off so well......
Mad Men such great writing and performances from all the cast.
West Wing.
24, again a great original concept then a few seasons in pretty rubbish, but good entertainment.
Lots of the 'big' ones ran too long started off really great and then downhill and the writing bad, ie The Walking Dead, Vikings, GOT, Orange is the new black, Breaking Bad and so on