Kado is a genuine attempt at a mature, intelligent, science fiction series that takes a First Contact premise and tries to work through the political and social ramifications using (for the most part) equally mature characters. This is a show where the default attire is business suits, not sailor suits.
Alas, the key word is attempt. Kado doesn’t quite, or hasn’t yet, succeeded in what it’s trying to do.
Koujiro Shindo and his offsider Shun Hanamori are senior negotiators for the Japanese Government. Episode 0 Ninovo sees them sent to negotiate the acquisition of a factory for redevelopment as a community hall by the government.
However it turns out to be much more complicated than that. Ninovo establishes Shindo as the sort of negotiator who will find out what’s really going on, and then take a third option that satisfies everyone if he can.
Then Kado, a 2 kilometre cube appears over Haneda Airport and absorbs the plane Shindo and Hanamori were about to take to an overseas negotiation. Oh, and the cube contains a being named Yaha-kui zaShunina who is essentially from another reality and is here to uplift humanity with advanced technology.
Shindo gets more or less drafted as Yaha-kui’s negotiator with the Japanese government.
As I said there’s a lot to like about Kado. There are adult characters tackling serious problems and for the most part attempting to do so politically first. The characters themselves, including the female negotiator Saraka Tsukai are well realised with plenty of depth implied. Her scepticism about the wisdom of Yaha-kui’s handing over unlimited energy/power to the human race seems well founded.
The general lack of military action, despite loud threats from the United Nations, again seems a refreshingly sane thing to see in science fiction. This is a series based on talking things out, with a heavy serving of “sufficiently advanced technology” and a side order of “information wants to be free”.
I like what Kado is trying to do, trying to examine, I don’t know that Kado is working as art or entertainment. I think it says something that the almost childish genius physicist Kanata Shinawa is the most fun to watch when she appears.
Kado may well be heading to the right answer, I’m just not sure it’s the right anime. At this stage I’m going to continue watching because it is fascinating stuff but I’m not sure how long that will remaing the case.
Here’s the fairly atmospheric OP:
 Seikai Suru Kado, which I’m not sure of the accurate translation for