Happiness, when I heard the name, I thought it would be a rom-com, specially with Hyung Sik and Han Hyo Joo on board.. Totally unexpected setting, a very interesting start, questionable actions by a lot of characters, you find them dumb and stupid until you finish and really think about the situation they were in.

To be honest, until we are dropped into a hellish situation where there is no food, no water, no protection, no electricity, being completely oblivious from the outside world.. Leaving them completely clueless about when they can get out, and where each and everyone starts doubts the person next to them..

We cannot really judge them for doing stupid things, because in such a scenario nobody would be sane.

It's easy to think that why did he do that, he could have done that, because we are watching from a third person perspective, but in a similar situation most of us would probably end up doing similar things..

So in the end, I think the 'stupid' 'dumb' things the characters did, were not non-sense or not logical, because many of them already were 'lacking' many things in life or some of them were already devilish in nature. Their actions were based on what they had gone through in their life..

Might be a stretch, but some of the characters fit into the list of sins really well.. Some had multiple traits even..

Pride - Oh Ju Hyung / Doctor (Who thinks everyone is beneath them)
Lust - Koo Hae Song / Attorney (Who craved into lust)
Gluttony - Kim Dong Hyun / Vlogger (His hunger for content was unbelievable)
Greed - Woo Sang Hee (Her desire for crypto never ended till last minute)
Envy - Cleaner Couple (They risked everything to get what others had)
Wrath - Andrew / Murder (No need to even explain.. )
Sloth - Kim Jeong Gook / Police Detective (He didn't want to be involved with anything.. )