One of the most laudable entries on the recent festival circuit is So Yong Kim’s Treeless Mountain, which has racked up awards at Pusan, Dubai and Berlin. Following her 2005 DiY breakthrough In Between Days, Kim revisited the stories and settings of her childhood in Korea to film a stoic yet deeply affecting chronicle of two young sisters fending for themselves after their mother disappears from their lives. The film recently enjoyed a NYC unveiling at New Directors/New Films, and opens in limited release April 22.

In her review of the film at its Toronto premiere, Karina was most taken by the performances, which, she writes, “are all the more impressive considering the fact that the film’s two young stars are non-actors–––Hee Yeon Kim [who plays older sister Jin] was found in an elementary school in Seoul City, while five year-old Song Hee [as younger sister Bin] was auditioned along with her fellow housemates at a Korean orphange. Hee Yeon Kim’s performance as Jin is absolutely mind-blowing: trudging along with a sadness in her eyes that could only be described as world weary, she’s like a little adult trapped in the body of a girl barely old enough to go to school.”

While the performances of the children are indeed revelatory, there’s a lot of work going on off-screen to pull them off, amounting to a unique strain of filmmaking that incorporates both strict preparation and flexibility, and rigorous screenwriting with documentary improvisation. I sat with Kim during the Berlinale (as she took a quick break between tending to her two children - her film, and her young daughter) to learn more about her technique for filming children and what it was like to shoot an indie film in Korea.

Spout: I’m amazed by how this film looks, in terms of capturing a child’s experience. The camera is very tight on the children and the things they see; you know and see as much as they do. The glimpses of adults and the adult world is fleeting. How did you develop this look?

Kim: In the beginning my cinematographer Anne Misawa and I talked about what I thought was important. One was that the camera is always at the eye level of the girls. Second is that we always shoot the close-ups first. The third is that I didn’t want so much to capture the landscape of Korea. It’s not so much about the fabric of Korean society but a more about the internalized experience of these girls.

Was there a practical reason to start with the close-ups? Was it easier for the kids?

It’s very practical because the first two or three takes are the best. You can’t do too much blocking with them. The best you can hope for is that the camera is on their expressions as they’re sitting or playing in the room and capture that. Because to me that’s the whole movie. Especially with these two girls; they look so amazing. They have this innocence that you see in children, yet there’s so much there. They’re not a blank canvas at all. I think adults have this assumption that children don’t have that much depth, but I go with the assumption that they have so much depth that hasn’t been tapped into yet. That’s what the movie is about. For the older character, Jin, that’s what’s being drawn out of her, but it’s all within her already.

This is a story that could easily succumb to melodrama, but you shun it. It’s almost like watching a documentary. Do you have a background in documentary filmmaking, or how has that genre influenced your work?

I love documentaries. I wish I could be a documentary filmmaker. I tried to make a documentary when I was in Iceland. I was constantly involved in front of the camera, talking to the subjects. I got too involved with the documentary story, so it was terrible. I’m amazed by documentary filmmakers, because how do you stay faithful and honest to these real people.

My first film In Between Days was heavily influenced by Rosetta by the Dardennes Brothers, and they come from documentary filmmaking. I have a lot of gratitude towards them for the way they work. I’ve worked on [husband] Brad Rust Grey’s films, and his way of working has influenced my way of working. For me this film is a lot more formal. I don’t see the film as autobiographical, but I’m really grateful for being able to use personal experience as a motivating factor to get the story going and also to help shape it.

How did you adapt your experiences so that it became its own being and not a literal transposition of your personal history? What are the fictional creations that you are most proud of?

A lot of things that the kids do together were made up on the set with whatever we had available. Almost everything was a combination of something made up on the spot and something written. It kind of drove the Korean crew and the producers crazy, because in the mornings it could be a completely different schedule than what it was the night before, because it depended on the moods of the girls and what they might be experiencing that day. One day were were supposed to shoot the piggy bank scene, and the piggy’s eye fell out. Of course I had no idea that the piggy’s eye would fall out, but it fell out. And I said, “Hey Bin, how about sitting here and coloring the piggy’s eye in?” So she’s coloring the eye in, and I would say to her, “Say, ‘Piggy, when is Mommy coming back?’” or “Can you ask the piggy if it feels better now that you fixed its eye?” And she would say that.

So how much did you shoot in sequence? Was that the original plan?

There were three main locations: Seoul, the aunt’s house, and then the countryside. That was sequential, but within those three chunks it was mixed around. By the time we got to the farm, the kids were so exhausted. These kids had been working every day for the past 25 days. So for the last four days they were exhausted. And the last shot of the film, of them walking home through the field, was the last morning of the shoot. They were so excited.

How much of the story did they kids know going into the filming?

They didn’t know anything about the story, except the older girl’s mom read the script and explained the story generally. Every day, even with the scenes we were shooting, the kids wouldn’t know what it was about. Thankfully they wore the same costumes almost every day, so in the scene where they’re playing with the piggy bank, they end up fighting, and we used the fighting footage in another scene. So it was very flexible.

When I was preparing and writing the script, I read about directors like Kore-Eda Hirokazu and Jacques Doillon and how they worked with kids. I’m so thankful for them. I found out that for Nobody Knows, Kore-Eda had a very small crew, and he worked with the kids and shot over a long period and let them do what they would naturally do. And it was inspiring to see these moments that he’d gathered over a year and to see the seasons and how things developed. And I knew I wouldn’t have as much time as he did, so I had to make sure that things happened for these 29 days and that the kids would be themselves and that the crew was small so they’d trust us.

For the two of them, I worked with them in the beginning like it was a game with rules. And the rules were simple: 1) never look at the camera, 2) never look at me, and 3) always repeat what I say. So it was very simple. But these two kids were amazing. The way we cast them was that I went to all these schools to obsere kids and after observing the classes I’d pick out two or three kids that I thought were interesting and I’d do video interviews with them. And during the interviews I’d give the kids instructions, like “Count to 10. Go to the corner. Look out the window. Count to 20. After you count to 20 come back to me and look back into my eyes for five counts, and then go out the door.” So I’d give them instructions like this to see if they could follow.  I went through hundreds of girls like this.

Doing that with the two girls makes it sound like a game. But doing that every day for hours over several weeks must have been grueling. How did you sustain their commitment throughout the shoot?

Well it’s hard for even the crew to go through that kind of rigorous schedule. These girls were amazing, but of course they’d lose it several times during the day. Everyone goes through these cycles, where they feel energized in the morning and then in the afternoon they are low energy, and we take a break and then they come back. We cut back on our daily schedule. We’d shoot the kids from 9 to 7. Crew times started at 8AM and we’d be done by dinnertime. The older girl’s mom was there so she had a fulltime caretaker. The younger girl had my assistant as a fulltime caretaker. One thing we tried to do was not to bribe them with things, like cakes or cookies or toys.

So did you talk them through their bad states?

I’d shoot them. As they’re crying or having a breakdown. Because I needed those moments, and I’m a selfish director, so a lot of those crying moments in the films were when they were just exhausted.

How much of an adjustment was shooting on Super 16 after shooting on DV for In Between Days?

It was a huge adjustment. We used the ARRI SR-3. It was so heavy and the magazine was noisy. We shot mostly on sticks, and I’d originally wanted to shoot handheld like the Dardennes’ Rosetta. But we tried on the first day and we had to abandon it, because it was very distracting for the kids. But I liked how it ended up looking calm and composed.

And things you do with staging and rack focus is so precise. And still it allows for incredible moments. Near the end there’s a scene where the older sister Jin asks her grandmother for new shoes and then she notices the holes in her grandmother’s shoes, and you can practically see the lightbulb go in her head: “Grandma doesn’t have new shoes, maybe I shouldn’t ask for them either.” How do you capture that? There’s almost no way you can direct that with a child actor.

Yes, it’s a miracle. We shot 40 hours of footage. With a shot like that you can only imagine how many takes we took. With a moment like that you can’t tell her how to look, or it will come off as false, because the kids are so transparent. So it really is a miracle.