In Park Chan-wook’s romantic-mystery film, Decision to Leave, detective Hae-joon (Park Hae-il) falls in love and gets obsessed with his suspect, the widow Seo-rae (Tang Wei). Directed and produced by Chan-wook who co-wrote with Jeong Seo-kyeong, the movie bagged the Best Director award at this year’s Cannes Film Festival.
Asked in an interview via e-mail what inspired him to make this film, Chan-wook replied, “My first source of inspiration was Martin Beck, the protagonist of a Swedish novel series. He does not use violence nor is he a genius; he is merely a diligent policeman who is kind and generous.  Thinking about this character led to a question in my mind that sparked my imagination: what if this man falls in love with his female suspect? The character Hae-joon Jang ended up far from the character of Martin Beck but that was how it all started.
“Secondly, I became homesick while working on postproduction for The Little Drummer Girl in London. I began listening to different Korean pop songs. ‘Mist’ was a song I enjoyed since I was young, but I was not mature enough to appreciate the lyrics of the song at the time.
“Listening to it again in London formed an image in my head — an image of a person finding a blurry silhouette of a lover of the past on a street filled with mist. He or she squints and tries to get a closer look at the silhouette. I wanted to make a film that captures the pitiful emotions of that person.”
For the 59-year-old filmmaker, the most challenging aspect of making this movie was Chinese actress Tang Wei’s Korean. He explained, “She jumped into the project without speaking a single word of Korean. But she did not want to merely memorize the sounds of the words and imitate the language.
“She learned the grammar and memorized the other characters’ dialogues. That’s how she reached a level of Korean that is fluent enough for Korean audiences to understand. She even crafted different nuances I wanted by changing things on the spot. She had to, at once, speak a language that was difficult for her while also conveying the complex emotions of Seo-rae with her eyes. I only have utter reverence for her efforts.”
Chan-wook revealed that he wanted to work with the actress ever since he saw Lust, Caution: “You can say this is a wish that took 15 years to fulfill. I could not find a project to work with her since she did not speak Korean, so I decided to create a character from scratch to fit her circumstances.”
As for Park Hae-il, Chan-wook said that he met him for the first time when he visited the set of Memories of Murder to see Bong Joon-ho.
“And for the next 20 years since then, whenever we hang out together with other friends in the industry, I have always been amazed at his consistent character. He is an honest and truthful person. That is why I had him in my head even from the early stages of developing the character Hae-joon. You could almost say Hae-joon was modeled after Hae-il.”
He added, “This was a film that could not be made without those two people. Differently put, if I failed to cast them, there was no point in writing the script at all. Hence, I met up with them even before writing the script. I told them the story we were developing verbally. Luckily, they both agreed to join me on this journey. I had the luxury of writing a script with my leading actors already cast.”