Question about the ending (spoiler)

That's what I thought she was doing at first, or at least trying to hurt herself, but I believe it's very hard to kill someone using a single acupuncture needle, especially on the thigh. Then I remembered when she was talking to the junk collector, he said that he'd witnessed something horrible and she said she knew how to stick a needle in one's thigh to make oneself forget bad memories. Whether that's true or not, she certainly believes she can make herself forget via acupunture.

But I really like your interpretation that it could be her death. I think the first two things you mention might just be coincidental, but the dancing part makes sense. When she danced in the beginning of the film, it had a sort of "afterlife" feel to it. I don't mean literally, like she died and went to wherever, but just like..the character passed through some kind of emotional threshold because of whatever will be shown in the rest of the movie. The kinds of dances she does in the beginning and end are fun, happy dance moves that old people in Korea do at celebrations. But in spite of her dancing, she looks dead and hollow. So I guess she probably doesn't die literally, but she wanted to start over fresh by erasing those bad memories, but in the process, a part of herself died.

it's been a while that i watch the film, so i don't remember exactly. But the needle at the last scene means that she tries to forget what she did. (I think in the previous scene in the middle of the film, there was some mention about this.)

Nah, no way! Why do think she mentioned the acupuncture point on the thigh so much? She didn't kill herself, and the fact that she murdered the trash collector pretty showed she'd never abandon her son, in fact, the whole movie showed that.

No she wasn't killing herself.

She took the "Parent's Appreciation" trip to get away and forget everything that has happened for the past couple of weeks.

Why did she put an accupuncture needle in a pressure point in her thigh?

Earlier in the movie, she mentioned a pressure point in between the thigh that can block out bad memories. This is what she was doing. She was trying to erase the "nightmare" she has been through. Hence, the ending: after inserting a needle to the pressure point, she started dancing with the other parents....

I guess, ignorance is bliss.

The mother mentions earlier in the film that there is an acupuncture point on the thigh that causes the person to forget - she does this to herself to help her get over the painful memories of losing her son, committing murder and realizing she cannot do anything else to save him. He is an adult now who must deal with his own mistakes, and she must learn to move on with her life. I think this was just a visual metaphor to show the audience that she has started to become her own person.

"because he never remembers anything and he certainly wasn't intelligent enough to put two and two together."

I disagree that he wasn't intelligent enough to put two and two together. I think the major clue to the fact (imo) that he knows (or will know) she killed the trash collector is when he remembered from when he was 5 years old that she tried to poison and kill him. To say he never remembers anything is discounting a lot of the events in the movie, and I think that moment proves he was intelligent enough to put two and two together. Although he may not realize it right away, eventually the connection will pop into his mind. That was shown again and again throughout the movie, including when he remembered that he did not break the rearview mirror on the Benz, even though he was blamed for it originally.

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Dyin' aint much of a livin', boy.

something that struck me was his tone when he was tellin her that she shouldnt just leave her things lying around. there was a sense of urgency and fear in his voice, and he was being secretive about it. if he had no idea, he would've been happy to give his mother her little kit back.

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He probably knew what he had done, at least on some level, hence is explaining to his mother why he thinks the murderer put the girl on the roof.

I doubt he knew what his mother had been up to... not that it would matter much if he did. He wasn't together enough to comprehend the moral ramifications of it all. Thus she was alone in her anguish.

As others have said, her putting the needle in her thigh was intended to "fix the knot in one's heart" and help her forget. I'm not inclined to believe that such a thing can be done, but the obvious point was that she intended to suppress her feelings of guilt - as she had done after poisoning her son.

Heartbreaking story. And, on one level, so real - the shenanigans parents get up to in an attempt to "help" their children/family which often results in psychological scarring is brilliantly dramatized in this movie. This is arguably especially true of Korean parents, as they are rarely the sort of people to do things in half measures, and thus more prone to tragedy - haha.

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It's a movie, people! It's not, nor is it meant to be, real life!

I agree with a previous post that the son seemed to be getting better. In fact, just as he seemed to be able to feed himself in one of the last scenes of the movie- he also poured a glass of water for himself and his mother. At the bus terminal- he was the one getting food for his mother. She told him he had gotten too much. In a way it appears that he now can reciprocate taling care of his mother as well- and thre is a strong bond between them for what they had both done.

She was obviously devasted when the other mentally challenged boy got charged with the murder and cried when she asked if he had a mother and he said no. Not sure if the son remembered what he did- and his explanation of why the girl was dragged up to the rooftop could mean he either remembers or that subconsciously he remembers and is musing to his mom about the reason.

I think he makes some connection his mom was at the junk collector's home and bunred it down- and he in turn was protecting her by giving it back to her. That was just the impression I got.