I have watched this movie because it was directed by Bong joon ho(Parasite). But what gripped me was the acting of Kim sang Kyung. It's a classic Bong joon ho movie, it uses humour not to foreshadow the dar aspects but rather to take you through a roller coaster of emotions peaking at the end. The mystery continues till the end and makes sure you are hooked to it until the dark of it locks onto you.