I am generally not even a horror fan, but this series was so thrilling and tense I was glued to the screen through all 10 episodes without a second of being bored or even remotely thinking about fast fowarding. (which I have to admit happens more often lately, when dramas have a good start, and quickly go downhill either with storyline, dragging etc.) I also found it remarkable that (after I have watched several 'end of the world/zombie apocalypse etc. shows in the past years) in this show they at least didn't shy away from the fact that in such circumsatances also the worst in humans comes out and things like rape would happen. Other apocalyptic shows go on for 10 seasons and never even mention it, like it wouldn't happen - and it would!

I do not know the webtoon but I can say pretty much everything in this adaption is perfect for my taste. The storyline, the actors, the soundtrack (phenomal), the production, the lighting, the sets, the special effects, and especially the whole atmosphere created in this huge building - really got me and I felt like I was sitting motionlessly tense watching, only interrupted by really well done monster sequences that got me shrieking out loud.

Still, in all the horror story there are serious and good single stories of the main characters.
It even managed to get me crying at one point when Jung Jae-Heon sacrified himself with his spirit true to the very end in all that dystopic mess of a world.

if you generally like the genre I'd say this is yet one of the best shows I've seen and from the first to the last episode.