One of the most shocking moments in Parasite happens in seconds.
Mr. Kim, or Ki-taek, grabs a knife and kills Mr. Park in the middle of the chaotic birthday party.
But why?
Mr. Park never physically attacks him. He does not even know that the dying young woman is Ki-taek’s daughter.
So why does Ki-taek suddenly murder him?
Years after the movie’s release, viewers are still arguing about this scene.
And no — it wasn’t simply because Mr. Park complained about his smell.
The Smell Had Been Following Ki-taek
Smell appears repeatedly throughout Parasite.
The Park family’s young son first notices that the new driver and housekeeper somehow smell alike.
Later, Mr. Park describes Ki-taek’s smell as something associated with people who ride the subway.
Ki-taek secretly hears him.
That matters.
The Kim family can change their clothes, jobs and behavior. They can pretend to be tutors, drivers and professionals.
But they cannot completely hide where they come from.
The smell becomes something Ki-taek cannot escape — a reminder of his poverty.
Then Everything Collapses
Before the birthday party, Ki-taek’s semi-basement home has been destroyed by flooding.
While his family loses almost everything, Mrs. Park casually talks about how the rain has made the weather beautiful.
Then Ki-taek is expected to return to work and entertain the Park family’s son at a birthday party.
By this point, he is emotionally exhausted.
Then violence erupts.
Ki-taek sees his daughter Ki-jung bleeding badly.
People are screaming.
But Mr. Park is focused on getting his own son to the hospital and demands the car keys.
From Mr. Park’s perspective, this makes sense: he is desperately trying to save his child.
But Ki-taek experiences the moment very differently.
The Final Trigger Is the Smell
The keys fall beneath Geun-sae, the man who had been secretly living underground.
Mr. Park reaches toward him and recoils from his smell.
He covers his nose.
Ki-taek sees it.
That tiny reaction brings back everything.
The comments about his own smell.
The subway.
The flooded semi-basement.
The invisible “line” between employer and employee.
And now, while Ki-taek’s daughter is dying, Mr. Park is once again disgusted by the smell of someone from the very bottom of society.
Ki-taek snaps.
He grabs the knife and kills Mr. Park.
But Was Mr. Park Actually Doing Something Wrong?
This is why the scene remains controversial.
Mr. Park does not know Ki-jung is Ki-taek’s daughter.
His own child has collapsed, so naturally he wants to reach the hospital as quickly as possible.
Some viewers therefore argue that Ki-taek’s reaction is unfair — even irrational.
They have a point.
But Parasite does not present the murder as a rational decision.
It is an explosion.
Bong Joon-ho himself explained that Mr. Park’s intense reaction to Geun-sae’s smell was designed to become the trigger for Ki-taek.
The smell is not the entire reason.
It is the final insult after a lifetime of humiliation.
That distinction changes the ending.
Ki-taek does not kill Mr. Park simply because one rich man thinks poor people smell bad.
He kills him at the exact moment when every invisible class barrier in the movie suddenly becomes impossible for him to ignore.
And that leads to an even harder question:
Was Mr. Park actually a bad person at all?