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The making of

The Host

From crafting its amphibious mutant monster to shooting in Seoul’s rat-infested sewer waters, how Bong Joon-ho’s ‘crazy idea’ from his school days was created


The success and resulting familiarity we have with Bong Joon-ho's 2006 monster movie can detract from the adventurous, and potentially obscure, nature of the film’s premise. 

It is worth laying it out in basic terms – a US military pathologist orders the dumping of 200 bottles of formaldehyde resulting in the growth of a large amphibious mutant which launches itself from the Han River to gobble Seoul-siders and kidnap a schoolgirl. 

While Director Bong had established remarkable levels of good will in the wake of crime mystery masterpiece Memories of Murder in 2003, The Host is still an ambitious project to make a success. 

A success it was though, at the time becoming the highest-grossing South Korean film of all time, then a US release and various international DVD and Blu-ray incarnations. 

So how did Director Bong, cast and crew manage to pull it off? To answer that, we must return to Bong’s school days... 

Monster inspiration 

“The first notion came to me in high school, a crazy idea,” says Director Bong. “What would happen if something like Scotland’s Lock Ness monster appeared in the Han River?” 

Bong explains that as his debut feature Barking Dogs Never Bite was premiering in 2000, the McFarland Incident was “exploding in the press”, where a Korean mortician working for the US military in Seoul was ordered to dump a large amount of formaldehyde down the drain. An environmental outrage, the incident also sparked hostility towards the US.


"In that moment, I thought, ‘This could be the starting point for my story,” says Bong, who explains the vision of the dumping of toxic chemicals came to him “as if I had witnessed it myself.” 

“This could be the background for the birth of our creature,” continues Bong. “This is the opening of a movie. There’s that movie Signs from M. Night Shyamalan that shows Mel Gibson and his family battling with aliens. It was a movie that dealt with aliens in a really unusual way with a story that unfolds by putting a big emphasis on the family. I was influenced by that too.” 

“It was about four years earlier [than 2006],” says executive co-producer, Choi Yong-bae. “That was when Director Bong first proposed his idea to me that a monster would appear in the Han River. A monster movie about a creature that comes out of the Han River? I thought it was a movie worth trying to develop.”

“He’s [Director Bong] not the type to joke around even though I said: ‘Is this for real?’ at first,” says director of photography, Kim Hyung-goo. “I was both excited and worried about how to pull it off. It was really intimidating at first.” 

Penning the script 

Back in 2003, Ha Joon-won joined Bong to start the script, then in December 2004 Baek Chul-hyun joined the process to revise the script. 

“At the script stage, first we went to the National Library,” says screenwriter Ha. “I read a lot of science dissertations. I studied the details by looking at the photographs. I studied the reproductive stage of leeches. How those things mate and how they reproduce and even about how they might mutate.  

“At the very beginning stages, after going through that process, we were getting close to the idea of the creature,” says Ha. 

“If you focus on the plot, it’s a movie about a kidnapping,” says Bong. “Performed not by a criminal, but by a monster. It’s not about showing a family's struggle with a monster. If you really want to nit-pick, it’s a movie about a family striving to save its daughter.” 

Bong says the plot was conceived with the idea of a monster carrying off victims, “that was really crucial, the concept that first occurred to me,” says Bong. “They want to go and search for their daughter. Because of the virus situation and the Han River area being cordoned off and the family having been put into quarantine, they’ve developed a lot of handicaps.  

“The family has become a target pursued by the authorities, police and military. So those premises formed the most fundamental basis for the film’s script,” says Bong.  


Composing the characters 

Bong says it was important the main characters were not ones you would expect to see fighting face-to-face with such a creature.  

“So we took people around us, people we see every day, a lower-middle class family without a lot of resources. The main characters were kind of losers,” says Bong.  

“That was more suited to the tastes and spirit of our movie. We set up the main characters as an everyday family running a food stand by the side of the Han River,” says Bong. 

Ha explains that in the script writing stages, most of the casting had been decided and that knowledge was used when writing the screenplay. “We chose characters with names similar to the names of the actors and because he [Director Bong] knew the actors well he was able to form the characters in an even more interesting way,” says Ha. 


Setting the stage 

The Han River is a vast expanse. Nearly 500kms in length, it begins as two smaller rivers in the eastern mountains of the Korean peninsula and converges near Seoul. A water source for over 12 million South Koreans, it is also one of the most iconic elements of the country and Seoul in particular.  

“We had already scouted it [the Han River] extensively on foot,” says Ha. “At the pre-production stage, in terms of Han River pictures alone we had 5,000 or 6,000 pictures to work with. After amassing spots all along the river, we had many locations that made people ask: ‘Are there really places like that along the Han River?’ Knowing about these spots really helped in writing the script.”


“The stand operated by Gang-du (played by Song Kang-ho) and Hee-bong (Byun Hee-bong) is a real stand located near Seogang Bridge,” says Bong. “That area near Seogang Bridge is the most crowded along the Han River. In the scene where Nam-joo (Bae Doo-na) gets a text message and runs to save Hyun-seo (Go Ah-sung) she runs across a bridge over the Han River. The bridge itself and the view from it are very familiar to what we often see [in Seoul]. And the scene where the family battles the monster is set on Dongjak Bridge, which is in the centre of the Han River.” 

Bong says the most important spot in the film is where Hyun-seo was held captive and this is a real location. “We were really excited, like: ‘Wow! A spectacular, overwhelming space like this really exists!’ We were really happy about it. We said: ‘Let’s set this space up as the monster’s lair!’ and we wrote the script accordingly,” says Bong.  

“I imagined that a real-life monster could actually live in a place like that so I started using it in the script,” says Ha. “But in reality, people would ask me if that location was digitally created or a set. It was a location mistaken as a set.” 

“Instead of trying to imagine a place,” says screen writer Baek Chul-hyun, “we agonised more over how to structure the story around these real-life places.” 

“The feeling that the director wanted to express with The Host was rather than something horrible and scary, was a feeling of something vacant or missing,” says production designer Ryu Seong-hee. “The creature was meant to impart this feeling, so I first got a sense of what the film should be like through the work done in pre-production.” 

“I had to agonise a lot in order to meet the prerequisites for filming,” says co-producer Joh Neung-yeon. “Because it was shot near the Han River where it was crowded, I knew it would be very difficult to shoot. How to shoot the film there was something our production team, direction team and many other teams were quite worried about.” 

Training the cast 

For this humble family set to duel with a powerful monster, Director Bong turned to the experienced Byun Hee-bong as Park Hee-bong, father/grandfather and owner of the food stall, whose first film was in 1980 and appeared in both of Bong’s prior features – Barking Dogs Never Bite (2000) and Memories of Murder (2003).  

Bong also turned to two other Memories of Murder stars in Song Kang-ho as Park Gang-du, Hee-bong's oldest son and Hyun-seo's immature father, and Park Hae-il as Park Nam-il, Hee-bong's younger son and jobless college graduate. 

Bae Doona, cast as Hee-bong's youngest daughter and competitive archer, had spent the 2000s in Bong’s Barking Dogs Never Bite and hit films such as Take Care of My Cat and Sympathy for Mr. Vengeance. Completing the family was Go Ah-sung as Park Hyn-seo, Gang-du's daughter, a debut role that would launch a prolific career, including working with Bong again on Snowpiercer (2013). 

Despite the acting propensity of this carefully assembled cast, the film’s action set-ups demanded specific training to perform. Most notably was the need for Bae Doona to fling arrows like a professional.  

“I liked the idea of someone fighting a monster with bow and arrows,” says Bong, who explains that Cho Choon-Bong, an archery coach, was recruited to train her.  

“When she [Bae Doonna] was training, I visited and took a few shots under Coach Cho’s direction,” says Bong. “It’s definitely not just any sport. She shot well enough to be recommended for amateur competitions and she enjoyed it too. She was rated from eight or nine points shooting at a range of 50 metres. So it wasn’t computer graphics, she actually made a nine-point shot.” 

For Byun Hee-bong and Song Kang-ho, they were taken to a clay pigeon shooting range to hone their gun skills. Behind-the-scenes footage shows Bong explaining to Byun that he must learn how to shoot high as the film calls for shooting the monster as it swings from a bridge.  


Memories of the sewer 

While the cast may have enjoyed their shooting training, the most memorable part of creating The Host might have been the most uncomfortable – heading directly into Seoul’s real-life creature-filled underground sewers. 

To make this possible, the entire cast and crew, including Director Bong and a needle-petrified Bae Doona, all had tetanus shots before going into the sewer.  

“The stench was beyond imagination,” says director of photography, Kim Hyung-goo. “It really grosses me out to imagine what creatures could actually live here. We had to get shots. [You] don’t know what creepy-crawlies we might run into.” 

“I didn’t know these sewers existed in Seoul,” says martial arts supervisor, Yang Gil-young. “I was shocked by the smell. But the size, the scale – it was stunning. I thought that someone could hide here a long time without getting caught.” 

“I have done thing that I’d never have done in my entire life,” says Song Yong-woon from the production unit. “No good memories of the sewer experience”. Song explains that as it was the winter, the bottom of the sewer would freeze and a rocket-shaped heater was needed to thaw the ice.  

“Once someone turned a flashlight on and the black floor suddenly turned all white. Because the mosquito larvae reacted to light and spread all over the surface,” says Song.  

“There is this worm called a blood-sucking tapeworm,” says assistant production manager, Joon-yeob Lee. “This worm apparently lives only in rotten debris and, boy, we were scared. It burrows into your skin, lays eggs, and the larvae spread all over your body. It’s very scary.” 

“In some scenes the actors had to roll around in raw sewage,” says director of photography, Kim Hyung-goo. “I thought, there is no way we can actually make them do this. So we seriously considered building a set and also agonised over how to bring a camera in the sewer. The truth is we did this because it’s in Korea. If it was Hollywood we would have built sets.” 


“Mr. Bong then discovered a dead fish in the entrance,” says Lee Won-hee from the directing unit. “He said ‘I found something at the entrance and I love it’. So then we were told to collect dead animals around that area. Fish, pigeons, drowned rats with bloated bellies. We piled them up using sticks, but by the time we shot it once they all got swept away by the current. We didn’t want to lose them so we had to work hard to collect them back.” 

“To make sure the electric wiring didn’t get wet we had to tape the wires to the walls,” says director of lighting Jung Young-min. “The lighting equipment was standing in the water, basically. So the possibility of electrocution was a serious concern. There was limited space for equipment and we had to find the best angles. So it was pretty tough. I guess rats are inevitable when you’re in a sewer, but there were also bugs, some invisible.” 

Jung says there was no difference in the degree of hardship between crew and actors. “I feel like these hardships were what produced a great movie,” he says. “Plus, we learned new things about the Seoul sewage system. I don’t know if they’ll make any more movies set in sewers but it was a good experience for us and we accumulated a lot of know-how about filming under such conditions. It’s the same for any movie but in retrospect it was educational and fun.” 


Creating a monster 

Perhaps the most fundamental element of any monster movie is its true star – the monster itself. This will decide the entire tone of the film. If it was a monster that scared people, if it disgusted them, or if it made them feel empathy.  

“At the beginning I didn’t really have many thoughts about the creature’s form,” says Bong. “In Ridley Scott’s Alien, the creature had a normal size that felt realistic. So I thought the bigger the monster, the less real it would look. [I wanted] a size that feels realistic. A size that can be hidden behind a truck or a bus.  

“The monster has to be able to run on land and attack people walking along a riverbank. It would adapt to the environment along the Han River. I’d already imagined its unique movements on the bridge supports. These are the basic things I requested of various monster designers,” he says. 

Bong explains that as the monster was created by toxic chemicals dumped into the river, it originates from a type of fish. “It’s a mutant that is biologically mixed with an amphibian and a reptile. That’s why it has legs and stuff like that,” says Bong. “Basically it has a malformed, asymmetric body and feels pain all the time. It suffers from merely existing and is always hysterical with pain.” 

Bong says the imagery which really inspired him was that of “an insect stripping clothes off people before eating them just like a monkey peeling bananas”. Working with creative designer Hee-chul Jang, painter Ji-song Lee and eventually storyboard artist Ha Kwnag-min, Bong’s initial drawings were expanded into the final monster.  

“We worked on the form of the monster through trial and error,” says Hee-chul Jang. “First of all, I gathered a lot of examples of real-life malformed creatures. They included humans and animals like a cat with two heads and a number of similar cases.  

“I got lots of tips from such unnatural, abnormal phenomena. At first, I just drew as large a variety of monsters as I could. What I chose first was a mix of fish and amphibian elements,” says Jang. “For its torso and body, I often referred to eels for inspiration. And then I added forelegs.”  

After various incarnations, the monster was designed, but the vast task remained of bringing it to life. To assist in this, The Orphanage, a visual effects studio located in California, was recruited.  

“Their filmography was impressive,” says Bong. “Most of them worked on the Star Wars series and Jurassic Park. Because of such a filmography they were open-minded and progressive. While they were less expensive, in terms of quality or skill, they were no less accomplished than any other large, major company.” 

Bong says that because the selection of a visual effect company had been delayed, the Korea-based team had already carefully prepared more than 10 animatics of important scenes, allowing The Orphanage to more rapidly create the special effects.  

Some of the monster effects needed to be Seoul-based and were created from months of pre-production practice. One of the film’s most famous scenes, the monster dropping into the Han River, was created by dropping a drum barrel filled with 500kg of cement into the water.  

“This was needed in order to see the splash effect of water spreading,” says Kim Joon-soo, assistant director. “We were probably most happy with that effect during testing. The director also said, ‘That’s magnificent’. After we dropped it, we had to pull it back out again. That was the only way we could shoot many takes,” says Kim.  

The end result of all this toil was a monster movie to rank alongside any of its predecessors. The Host was a labour of love that sprung from a school-days Bong Joon-ho and needed a vast array of creative force to realise in its monster-sized final form.  

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