Photo: Han Myung-Gu/WireImage

Choi Woo-shik describes Parasite like one would riding roller coaster. At first glance, the movie’s log line sounds simple enough: a poor family goes to work for a rich family, in a drama about greed and wealth and class. But Bong Joon-ho has put together an intricate character study that mangles and mutates any expectations. Scenes are both hilarious and tragic, as Choi recounts, pathetic and gratifying. Choi plays Ki-woo, the son of the destitute Kim family, who hatches a plan to recruit his mother, father, and sister to pose as unrelated workers and infiltrate the home of the wealthy Park family. By the movie’s devastating end, the Park home has become, at once, a vision of freedom and a pristine prison.

When he was growing up in Vancouver, Choi says he wanted to become a theater director. “I didn’t know that I could act, but my friend told me, ‘Before you do directing, maybe you should try acting. It would be better for you. When you know how to act, it would help you be a better director.’ So I was like, Oh, maybe, okay, maybe I’ll try. I flew back to Korea to do an audition, and somehow I became an actor in one day.” He no longer has ambitions to direct, but he does want to make the jump from the Korean cinema scene (where he’s appeared in Set Me Free and Train to Busan) to Hollywood. In passing, I ask his favorite Hollywood actors, whose careers he’d like to emulate. “Shia LaBeouf. Timothée Chalamet, oh my gosh, so good,” he says. “Paul Dano. Lucas Hedges.” Knowingly or unknowingly, he’s listed male actors known for sensitive performances, people who could easily be considered his peers after his performance in Parasite, an idea at which he blushes. Choi talked to Vulture about working with Bong, calling Kang-ho Song “Papa,” and if he thinks Ki-woo could buy back Parasite’s house.

I know you worked with director Bong on Okja, but how did Parasite happen?

When I was shooting Okja, director Bong actually asked me to stay in shape. I was like, “What, stay in shape?” But he actually said stay skinny. So I was like, Oh, okay. Does he have work for me later on? But he didn’t call me after that. It was like four months later that he’s like, “Okay, I was writing this script and I think you could play this role perfectly.” He said, “Your father’s going to be Kang-ho Song and I can’t tell you much more of it.” At first I didn’t really know what’s going on, and I couldn’t even read the script. I didn’t know my name or the role. I had no idea what I’d be playing. He gave me a script after that and it was amazing.

Did you “stay skinny,” as he’d asked?

Actually, I became skinnier than I should’ve! I don’t usually stay on diets, but I was a bit nervous about this role. So I think I became skinny naturally; I was just losing weight.

What kinds of conversations did you have with him about Ki-woo, and how to bring him to life?

I always had the question asking whether Ki-woo is a bright kid or dumb. Does he do good in school? He failed the university entrance exam four times. But director Bong said that Ki-woo is a really bright kid, but he doesn’t do well on exams because he doesn’t have any vigor. He knows that he needs vigor when taking a test. When he’s tutoring Da-hye, he stresses that vigor is really important, but he lacks it. Director Bong told me, “Yeah, he’s a really bright kid, but you don’t have to act him like he’s a genius or something.” I don’t know the specific word for it in English, but Ki-woo is very smart.

The most important stuff about Ki-woo was the close bond he had with his father. In Korea, there’s this culture where young generations have to be really polite to the older generation, but that sometimes becomes very, really uncomfortable and sad because you always have to be polite. I had to break that.

Sure, it’s hard to grow into yourself, to assert yourself, when you’re trying to be polite and deferential.

Kang-ho Song, in Korea, is like top of the food chain. You have to be really polite to him, but that becomes sometimes really uncomfortable to him, and to me. I was being polite, but I actually tried to really get into character and be like a son in the mind-set, too. I always called him father, like “papa,” in Korean. Everywhere I go, even off the camera, I’ll be like, “Well, Papa, did you have dinner?” People are kind of surprised that I kept calling him papa after the movie. I still call him papa.

That’s really sweet. Were there other things you and the rest of the Kims did as a family to bond?

When I was shooting Okja, that was my first time actually seeing a trailer for actors. In the States actors get their own trailers, but in Korea all the actors group up in one room, and stay there together the whole day. We don’t actually have to make time for bonding together because we always just eat together. We stayed in the same hotel for like two months.

So it just happened naturally. That makes things easy.

Yeah, like, after work we would just have a casual drink together, or if I have something on my mind or if I’m worried about some scene, I would just tell them over dinner. “Papa, this scene’s kind of …” and I’d get advice from him. I still get advice from him.

Which do you prefer? Having your own trailer, or staying with your cast?

On Okja, they actually gave me a trailer, too, but it was so uncomfortable and awkward. Just staying there doing nothing? I think I prefer being in the same room with everyone.

Did director Bong show you any of the storyboards for Parasite? I saw a couple of them this morning, and they’re kind of amazing.

I think he actually had experience drawing comics! He draws really well, and he would draw our characters’ emotions [in the storyboards] too. I think that helped us a lot, too. We didn’t really have to rehearse, because when you look at the comics he tells you what to do, that’s the direction.

One of my favorite scenes is when the Park family comes home unexpectedly, and the Kim family hides under that giant coffee table. That looked almost impossible to pull off.

It was really awkward and funny for us to be under there. But when they were acting on a sofa, we weren’t there to watch them. They had really a minimum crew [for that sex scene] on that set without us. A funny thing about that — when we were shooting, we were acting very [much] in a comic way, but the cut in the movie came out really serious. At the time, though, we were holding laughs. We were being very drunk! We didn’t know what to do!

How big was that coffee table?

They designed it for the movie; it was actually made for us. They measured up the table so four adults can fit under it. I thought it was a designer table, but they actually made it for the movie. I think it was half the size of this [hotel] room.

And the house wasn’t real, right?

Yes, every location on this film is a set. It’s all built up. Even the semi–basement apartment where the Kim family lives, it’s a set, too. The Park family’s house, it was actually made of two sets: the first floor and second floor were built at different places, and the basement was somewhere else, too.

Something I’m really curious about is the importance of the stone that Ki-woo gets from his friend in the movie’s first or second scene. What did you think it symbolized?

Ki-woo, as a character, kept on saying it was really metaphorical. There was a lot of conversations about that stone after the movie. Everyone was asking me like, “Oh, so what did that stone actually mean in the movie?” But Bong didn’t tell us that it means something. He just told me to take care of it.

So it was sort of up to you to decide what you wanted it to mean? To decide what Ki-woo wanted it to mean?

Yeah. And now that I think of it, when I was acting I thought it was a responsibility, like the heavy responsibility of Ki-woo’s thoughts. It was his idea to go work for the Park family, right? So it was a really heavy responsibility for him to carry his family’s future. But Cho Yeo-jeong, the Park wife, told me while we were shooting that she thought that the stone actually meant, like, an easy way to get to his life goals.

Sort of like a shortcut?

Yeah, shortcut. So then, at the end, when he puts the stone down on that mountain, it’s his way of saying, Okay, no more shortcuts. I will try as hard as I can to make sure that I get the money to purchase that house. I liked that. What did you think that the stone was?

I did think it meant responsibility, but I also saw it as him leaving behind his naïveté. When he puts the stone back, it’s like he’s putting away childish things, that he’s ready to act more for his own interests and become more independent.

Cho Yeo-jeong thought about that, too, like, shortcuts were childish. Director Bong actually told me that it could be a gift because Min actually gave us that stone as a gift. I asked [Bong], “When Ki-woo brought that stone to the basement, did he try to really kill Moon-kwang or Geun-sae?” But he was like, “No, maybe it was a gift. Maybe he wanted to say sorry.” That made sense to me. Ki-woo isn’t a person who would kill someone. He would just go down there like, “This was a gift from my friend. I’m really sorry about what’s happened here. Here is my apology gift.” Maybe it was a gift! [The stone] means a lot. It has a lot of meanings, I think.

I love that reading of the scene, actually. Let me ask you this: Do you think Ki-woo saw anything in the Park family other than them being so wealthy? I don’t think of him as being greedy or jealous, but I’m just curious what you think drew him to them.

I think Ki-woo’s only goal was to carry his family. He needed money, and our family needed a job. I think they were just a method of getting money. I don’t think he actually thought about it more than, you know, getting paid. I don’t think the Kims are really ashamed of their poverty. We, as a family, are all so positive and we share a lot of thoughts together. We’re a really happy family; we’re just without money. Having money problems can make some families aggressive to each other, but the Kim family is really tight and happy together. I don’t think he actually saw a difference between the Park family and Kim family, just that one had more money.

I have to ask if you would actually read someone else’s diary, as Ki-woo does in the movie.

My girlfriend’s diary?

Sure. Would you ever read your girlfriend’s diary?

I don’t know, maybe.

You don’t know?!

I kind of understand why he read it! He said he wanted to know her better, to know her deeper. So, yeah, maybe, if I don’t know what she’s thinking.

Can you tell me what you think of the ending? Do you think Ki-woo could earn enough money to buy that house?

It was really touching. Really sad, terrible. I felt so sad for Ki-woo. Do you know about that song that plays after the ending scroll?

No, tell me.

I sing a song. There’s a song that plays during the credits, and director Bong actually wrote the lyrics. The song is about how Ki-woo spent his days trying to earn money to purchase that house. It would take 564 years for Ki-woo to actually save up the money in order to buy that house. It’s almost impossible for him to buy the house. When I first read it, I felt really sorry for Ki-woo, but I’m pretty sure Ki-woo is one of those bright kids. He’ll come up with some idea, and he would just go into the German family’s house, and I think he will rescue his father.