Few spoiler for the first half.
Masterpiece? Expectation? Are you kidding me? What a disappointment!
This is my first review for "..." (Answer at the bottm)
Kim Gi Woo (Choi Woo Shik) betrayed his friend who trusted him to take care of the girl he likes. Did he have no conscience? But Kim Gi Woo doesn't seem that serious so I just continue the movie. Later, all of Kim Gi Woo's family members got job at the same house. Everything is good and funny up to this point although the rich family is dumb.

After that, poor family went crazy and got drunk in the house. Then, they let the old maid came in. Then, their mum want to call police because of the old maid and hers husband. She must be faking or she is not in rational state because they were drunk. What comes worse than that is that old maid and his husband didn't make a negotiation after founding out that these people are family. Everything went chaos from drunk part to the end. It makes me cringe from that moments on. This kind of story line is too bad to call 'masterpiece'.
If the script writer is wanting to give lesson to viewers, they should show us the right way. Now, script writer is telling viewers to do opposite of every dumb things they did in a movie. e.g. no conscience, getting drunk, threatening instead of negotiating, no plan? (That is if you want to dig your own grave.), Trusting too easily, Greed, ...

For rich family, dumbness/navieness is at a whole new level. Why they trust people so easily? Why no private investigation for employees? Why they don't check where they live? Why no cctv or hidden cameras in the house when you are that rich? Why get male tutor instead of female tutor for their daughter? Because normally, parents like to have same sex tutor not to have any love relationship.
Park Dong ik (Lee Sun Kyun) hate the smell of Kimg Gi Taek (Song Kang Ho) so he could have told him to take shower well or bought a shampoo and soap that he liked or even told him to shower at guest room before work. Because he hate smell and he hate that his driver kept on saying "You do love your wife". It made me think that Park Dong ik (Lee Sun Kyun) doesn't love his wife. Why would he get serious and angry whenever Kimg Gi Taek asked that question?
From this whole movie, Park Dong ik's son, Da Song seem to be smartest because he is the only one who noticed something but still not smart.

In conclusion, the story is too bad and characters are too dumb. Acting and situational background music are great.
Parasite, Bong Joon Ho and the entire team took home four Academy Awards:
Best International Feature Film
Best Original Screenplay
Best Director
Best Picture
Anyway, 4 Oscar it got are right for this movie so I can agree to that. The movie has brilliant picture quality and good angles. But not the story/plot! "What a letdown".