To be honest I was considering to drop it up until around episode 6, the story was all over the place and to be really honest I didn't understood the plot at all.

Now that I finished it I'm not sure that I understood all plot points as well... I'm not sure if they were too complex to grasp them or too stupid to waste my time on them...

Another confusing part was the constant time skipping . You were not sure when a specific scene is happening now or is a preview for a later stage. There were multiply times when they did this for scenes that I consider OK to be used for (those who you want to know more about) but for scenes that you don't care at all as well. So they figured out that this approach adds suspense to the show... but when your scene doesn't add any suspense it's useless filling and it becomes annoying.

The most cringe part of the show was that annoying gesture with their finger... I know that it was the name of the show, but come on... don't add it after each conversation... it started to become so cringey that it was killing the acting and dialog.

After episode 6 the show started to pick up the pace and to form a concrete plot of some sort and it became interesting for me.

The ending was passable... maybe a bit too overly happy... but it was ok.

About the acting... I will probably get hate for this, but I'm not huge fan of Yoona acting... I felt that her portray in K2 was a little lifeless (but I considered that to be her character there) but I'm seeing the same acting in this show as well... it's a little bland and I didn't see her stand out from the other male/female cast. So while I will not say that her acting is bad... it's a little bit too similar to her K2 role and I wanted to see a little bit more from her. This is of course a personal opinion so take it with a grain of salt.

So if you are looking for a conspiracy show that lacks romance I can recommend it , it's a nice time waste... but it wont probably enter your top list.