I'm just half way through so far, starting episode 6. The series promised a lot in the first and second episode, I think, and was very big on simple set pieces and set moves, quite like how the original "3 days" film was. It was engaging and really attention grabbing and intriguing as you wonder how the 20th Century classic "3 days" film (immensely topical of our time - e.g. Dr David Kelly & the Iraq War) or the "6 days" book would be developed. Things have gone downhill in a way, and quite a distance from the simple set pieces and set moves. It's not bad, but it has just become a whole different kind of composition.
There are some great bits, the acting (also editing, pacing) goes downhill just where the ideas of the script get better, more detailed and interesting. (If not quite the screenplay writing itself). There's a lot that's good about it. It does seem from a third of the way through that the actors who were initially convinced suddenly aren't themselves quite convinced with their own project anymore. I was wondering if the bailiffs turned up to the studio and let them know they're out tomorrow. They're the ones who need to bring it off. Even those who are keeping up the ballgame more, such as Brendan Fraser starts to look a little like he's thinking "not too long left till dinner". William Hurt and Bob Bamalam are the exceptions, both excellent and actually getting better all the time, as the two opposing symbolic poles - Hurt the nicely quite caricatured flawed hero father figure, and Bamalam the cartoonesque villain as if from another species.
You have to question after a while if the early promise Irons brought is lost or if the intention was actually to show him as pretty hugely feckless, out of place as a contrast to the involved, mysteriously interwoven, complex, advanced proceedings going on around him. (Also as quite a contrast to the mature, capable, assured Robert Redford of the 1970s film.) It would be an interesting approach if so, and I can really see that working on a level. However, even then, altogether there seems to be a good deal that is interesting. But it doesn't seem quite to work very well as a well-planned, well put together, coherent whole which satisfies as one piece of TV.
I may edit this if I finish the series, to say I didn't have the whole vision by this point or something - who knows!? On the whole though, it's much better than most series of any nature for me. But then I can't stand or even watch fiction TV series at all, generally, basically having watched no more than around 4 in the last 25 years. And I know it's the right choice! Therefore, that I'm even watching this and saying there's a lot that's good about it and that it may work quite well on levels, means it might have to be close to 'king of the TV series" of a quarter of a century. For me, I have to add. Maybe that world just isn't for me typically. Or maybe it's a pile of something.