Well, I'm not sure where to start. I can start by saying tho, that my rating was strongly influenced by the ending, because honestly, what was that? It was so unnecessary, honestly, and so incomplete... I don't know. But we'll get to it later, I guess...

I really liked the first half. The idea was so good with the same feeling of anxiety you get from zombie dramas, but with completely different creatures. I wouldn't say scary but rather interesting, curious. There was drama, terror, anxiety, funny and cute moments. It had practically everything. There was a whole plot that grabbed me from the very first episode, which made want to continue watching, feeling excited. The sixth and final episode left me with high expectations for the second part, however those expectations were far from achieved. As it only had 4 episodes I was afraid that everything would feel a little rushed and incomplete, which I was right about.

Part 2 wasn't bad but it wasn't good. I thought it started well, seeing the kids with more maturity, more experience after a month has passed since Mr. Lee's death, but it all went downhill from there. 4 episodes where the main focus wasn't the spheres but more “mundane” things, if I can put it that way. The criminals, the deaths motivated by humans, etc. I thought it got away from the main idea, and I don't know if I didn't notice or didn't pay attention, but Wonbin simply evaporated after episode 6, along with those who were rescued. Maybe the latter I didn't notice, but as for Wonbin, there's no sign that he died, so where did he go? This was something that left me confused.

As for the ending, the best way to put it it's that it was one of those endings where you wonder if that's what you've been watching an entire k-drama for. Only 4 people survived, 4 of whom were, let's say, the “driest” characters. Don't get me wrong, because I like Kimchi and Nara, and I don't mind the other two. But they literally killed every single character that was once very important for the story to keep going, in seconds, not having any impact as individual deaths at all in the viewers except for the shock part. It was literally pointless. That's it.

2 years later, Kimchi appears doing the CSAT, explaining that they've supposedly created a tool to solve the problem and blah blah blah. What tool? How did they end the problem? We need more then just knowing that they somehow created something that helped. How did you get out that bloodied classroom? It's all made of loose ends. What were the spheres anyway? Where did they come from? Why did they attack people, because I'm certain that the reason behind that wasn't just like one of the criminals said, to wipe humanity as they are trash. We also can't know that for a fact of course since he only suggests, as a maybe situation. I don't know if it's just my demand or pure curiosity, but I thought it was all very incomplete, and above all, very rushed. It deserved a third part, if it wasn't for that ending. The plot, the characters, everything was so good and it was capable of so much more.

I would like to say that I recommend it, however I would be lying. It's unnecessary to watch 10 episodes that give you expectation after expectation only to end up heartbroken and more confused than you were at the beginning. Sometimes, ignorance is indeed bliss.