I watched the first 4 episodes and thoroughly enjoyed them. It's truly bizarre and interesting. There's a thread of dark humor that weaves through them.
It begins with a voice-over narration, so no matter how much the horror and science fiction genres change, some things remain the same:
The Kingdom Hospital rests on ancient marshland where the bleaching ponds once lay. Here the bleachers moistened their great spans of cloth. The steam evaporating from the wet cloth shrouded the place in permanent fog. Centuries later the hospital was built here. The bleachers gave way to doctors and researchers, the best brains in the nation and the most perfect technology. To crown their work they called the hospital The Kingdom. Now, life was to be charted, and ignorance and superstition never to shake the bastions of science again. Perhaps their arrogance became too pronounced, and their persistent denial of the spiritual. For it is as if the cold and damp have returned. Tiny signs of fatigue are appearing in the solid, modern edifice. No living person knows it yet, but the gateway to the Kingdom is opening once again.Each episode ends with Lars von Trier speaking to the audience on screen over the credits.
This is available as separate tv episodes via youtube in the original language with English subtitles. Episode 1 is embedded below:
The other episodes are linked from that one at youtube.
The book 1001 Movies You Must See Before You Die includes Riget and says, "The Kingdom's spare, but escalating, supernatural manisfestations are genuinely eerie, sometimes magical". Moria says,
The biggest downer about the film version is that after some five hours it ends with a frustrating ‘to be continued ...’ This was taken up with the lesser but nevertheless still enjoyable The Kingdom II (1997) where Lars von Trier, Morten Arnfred and the whole cast returned.Series 1 gets a 91% score at Rotten Tomatoes.