for a movie that's only 1 hour and a half long, this wasn't bad, but it might've needed a little more emotional substance. they didn't stress enough how "bad" the relationship between Yi Na and her dad was, tbh it just felt like common sadness, and the dad was a workaholic who tried to make excuses to leave his daughter for a couple of months because he didn't know how to deal with the loss of his wife, and basically they just needed therapy not a new house ;)
anyway it took them a few days or less for Yi Na to act "weirdly" and a few days later she went missing, so there was not much buildup.

I personally used to be a scardy cat and I don't know if I'm just older now or movies lost their fear factor, but this was heartbreaking rather than scary. especially with the background story of what started it all.

and speaking of how it all started it felt quite basic, plus it was resolved very simply and it didn't need the dramatic fight scenes.

and they only spent a few seconds on the other kids but I think that'd have been the breaking point for them, I honestly teared up on that subject but then it was suddenly over.

I also feel like they could've built a beautiful bromance and connection, tbh Kyung Hoon came in the picture, said 1 thing about why he's doing this and boom they were working and solving what took him 10 or so years to solve. there was no anticipation, no foundation.

overall the acting was great and I'm looking forward to what Yi Na comes out with next, that precious baby is really talented~

ps I never rewatch stuff ;)