🚨Obviously MASSIVE spoilers ahead!🚨
1. First, Bong Joon Ho and cinematographer Kyung-pyo Hong framed certain scenes so there's a clear line separating the rich and poor — the line formed where the windows meet separates Mrs. Park and Moon-gwang.
2. You can noticeably spot a collection of Alfred Hitchcock films on a shelf in the Park home — Bong Joon Ho revealed that Hitchcock inspired aspects of Parasite.
3. After Moon-gwang is fired, Mr. Park reveals that her only flaw was eating enough food for two — later, we find out that she was secretly hiding her husband in the basement.
4. The architect who designed the house is named Namgoong — in Bong Joon Ho's Snowpiercer, Namgoong is the name of the specialist who designed the security features on the train.
5. Ki-woo's forged certificate shows that he's a student at Yonsei University, which is where Bong Joon Ho studied sociology.
6. When we first meet the Kims, you can spot them drinking FiLite, which is considered a cheap beer — after Ki-woo and Ki-jung start working for the Parks, they can now afford Sapporo, a premium beer.
7. When you see Ki-jung eating the jerky, she's holding it in her left hand, then when the doorbell rings it's suddenly in her right — this is a continuity error Bong Joon Ho purposely left in the film for fans to spot.
8. Da-song's "self-portrait" might not actually be one — it looks like it reveals what Geun-se looks like long before we learn that he's living in the basement.
9. Ki-taek reveals that he once was a driver for Taiwanese Castella — this is the same shop that Geun-se opened and ultimately the reason he had so much debt.
10. When the Kims crash the Park house while they're away, "In ginocchio da te" by Gianni Morandi is playing in the background — in the 1960s, Morandi starred in several comedy genre films that focused on the differences between the poor and rich.
11. After spending the night clutching the rock, you can see that Ki-woo has an imprint on his hand.
12. In Da-song's room, you can spot the headdresses that Ki-taek and Dong-ik wear at his birthday party at the end of the film.
13. When Chung-sook is furiously cleaning up the house before the Parks return, she accidentally sweeps her phone into the trash.
14. In the beginning of the film, Ki-taek flicks a stink bug off the table. By the end of the movie, he's essentially seen as a "stink bug" in the eyes of the Parks.
15. And finally, Chung-sook jokes that Min should've brought food instead of the rock — at the end, Ki-jung doesn't get a chance to bring food to Geun-se, instead Ki-woo brings the rock downstairs, which starts the chain reaction of murders.
