I was having high hopes for this show because the casts are my favorites and the director is famous for his gory and violent scenes. I enjoyed watching the show because of excellent acting from my favorite actors and great cinematography.

Jung Hae In proves he is acting genius and master of genre, expressing various levels of pain realistically and perfectly acting with only one eye. Go Kyung Pyo’s acting as serial killer is refreshing and Kim Hye Jun facial acting is great but her action scenes are kinda lagging in some scenes.

But what I feel most lacking is maybe suspense/ tension/ story development? I didn't feel so much excited to know what would happen next (maybe because I got spoilers from behind the scenes videos that Disney+ released in advance before the drama's premier).
OST is nice with Haein’s sweet voice but using the same song repeatedly for many times (although it's necessary for the plot) made me bored.
CGI and VFX are great especially the tentacles used for regeneration.
The gory and bloody scenes are not that disturbing to me.
The chemistry between the casts is great but felt the kissing scene between DongSoo and Yirang is too early Lol.

At the moment of writing this review, people are making noise about the rear nudity of the actors which is nothing strange in acting field but it feels like they used stunt doubles for those scenes.
[Edited - Jung Hae In confirms that he used stand-in (body double) for nudity scene in an interview.
https://youtu.be/nAEMUGOsz4o]

The sex scene was unexpected haha but didn't expose too much.

The last fighting scene between DongSoo and JinSeop didn't help me to maintain suspense and the ending scene hinting for another season is unexpected.

Overall I enjoyed watching the great performance from my favorite actors but sense of satisfaction was not that much and probably I won't rewatch this show within a short period of time. However if there'll be season 2, I'll definitely tune in to explore their so-called new Connect World.