How ‘Decision to Leave’ Star Park Hae-il Worked with Director Park Chan-Wook to Craft a New Kind of Detective Story

When a man is found dead at the bottom of a mountain, his much-younger wife Seo-rae (Tang Wei), becomes the prime suspect. Hae-Joon (Park Hae-il) the seasoned detective assigned to the case becomes enthrawled with Seo-rae, an immigrant from China working as a nurse, as he questions her connection to her husband’s death. His initial interest soon becomes an obsession as their game of cat and mouse gives way to a romantic connection.

In Decision to Leave, Korean director Park Chan-Wook, the master filmmaker behind Old Boy and The Handmaiden, weaves together elements of a classic noir mystery with a twisted tale of forbidden attraction—complete with plenty of secrets, lies, and no easy answers.

Cast in lead role before production began, Hae-il worked closely with director Park, with the filmmaker tailoring the character to capture Hae-il’s idiosyncrasies and emotional nuances. The result is a multi-layered performance that unfolds in gentle waves until the very last scene.

Speaking through a translator, Hae-il joins Awards Daily to discuss his close collaboration with director Park and offer insight into the many spellbinding mysteries and intricacies of Decision to Leave.

Awards Daily: During your initial meeting with director Park, the two of you had this hours-long conversation where he talked you through the story. What was your big takeaway, your first impression of Decision to Leave? What was it that made you want to do the film?

Park Hae-il: Although I’ve known him for a while, I’ve never worked with director Park before. So being in that moment, the instant feeling I had walking away from the meeting was a very pleasurable one, such a euphoric experience. Just to hear him talk passionately about this amazing film he wanted me to be a part of.

I was really excited about this potential project that he was offering me. And I honestly could’ve said yes on the spot. But I intentionally waited a couple more days to say yes just to enjoy the thrill of what an exciting film this would be. I just wanted to let that euphoric feeling stay a little longer. So I waited three days to respond when I said yes to him.

AD: You’ve talked about how gratifying it was that director Park was so open to your suggestions on set. Can you tell me more about your relationship as collaborators?

PH: Director Park cast me before finishing the script. So I think he took me into account, my energy, and the aura that I have as a person. And I think he really found a way to blend that into the film and the character as he finalized the script.

Because of how director Park approached the film shoot, I think he really picked up on the small nuances of the way I speak, little accents. It also allowed me, as an actor, to fully utilize the small details of how I express my emotions. And he really took the liberty to extrapolate on that more as we shot the film.

I learned that director Park is a director who really listens to every little thing his actors and collaborators say and takes everything into account. He truly sees this as a collaboration. And because of that, as an actor, I was able to walk through and utilize every small emotion in a way that came naturally to me without being forced to play a character that I’m not accustomed to because I was really charged to elaborate on who I am as a person and the emotions I have as an individual.

And I thank director Park a lot for letting me be able to be that way and really be able to use my true emotions as a person, and I could use those tools as an actor to create a character.

AD: Your character begins suffering from insomnia as he gets drawn into this case; we see him physically present in many spaces but mentally elsewhere. How did you prepare for that physically and emotionally as an actor?

PH: This character, Hae-Joon, is supposed to be serving the public as a police officer and as a detective, someone who’s friendly and kind to the general public and the citizens. And also a detective who’s really good at his job. He’s also someone, as you said, with insomnia, someone who’s having a lot of personal issues. He’s trying to live according to the values he believes in as a person and as a professional. Still, he’s kind of going through a slump and having doubts.

I wanted to create emotion that’s relatable, that people can empathize with, of being an adult in this world. Being an adult is hard and what society throws at you really knocks you down. There is a lot of depletion of feelings and emotions in that state of lacking. Tang Wei’s character, Seo-rae, comes in as a suspect that I met as a detective, but also someone who is trying to fill the holes that I have as an individual and as a character.

That’s how I started portraying the emotional rollercoaster that’s about to begin in the film. Decision to Leave takes on the structure of a detective film, but in the parallel sense, it also creates this romance film and the emotions that go along with it. Because of the bilateral structure and the different genres that this film takes, I focused on trying to develop the relationship between the detective and the suspect and the dynamic and the chemistry of romance film between the two potential love interests—trying to really merge those two different emotions and feelings into one for the audience to feel,

We start with the typical relationship between a detective and a suspect, where they start doubting each other, but they also have this indescribable interest in each other. They start looking into each other and sometimes even becoming obsessive towards each other.

And I felt there were similarities to how one might be when trying to pursue someone. I found that to be the most interesting challenge, but also a very fun way to portray the different emotional drives that you see throughout the film.

And from Hae-Joon perspective, once he learns the truth about Seo-rae, everything that he had built, his pride, is shattered. It creates this tidal wave, this rollercoaster of emotions, throughout the film.

AD: The romance is so subtle. How did you approach portraying this complicated dynamic alongside Tang Wei?

PH: I first thought that Tang Wei and I had a really similar energy as people and we were on the same wavelength, so it wasn’t really difficult to relate to each other. There was always a language barrier, Tang Wei’s native language being different than mine. And in the film, she plays someone from China who isn’t fluent in Korean. So, in front of and behind the camera, we both worked on learning to communicate with each other, despite the language barrier. And I think that helped build the chemistry and showcase that to the audience.

Tang Wei gives such an amazing performance as an actress. She had to create this character who had something that she was hiding but was still inviting people to be curious about it. She was full of secrets, different layers, and hidden messages.

Hae-Joon is trying to understand the secrets and the hidden layers, creating this innate curiosity and interest. And as a detective, he slowly looks at every detail of her life, creating this delicate nuance and the tone that makes Decision to Leave such a good film. For example, in the scene where he’s watching her apartment through the window with binoculars, it creates this intimate tone that this film has that is very interesting and intriguing for the audience.

Director Park’s work has a tendency to really pick up every audience emotion and shatter it in a very abrupt way. But this specific film is actually very different in how he allows the audience to be more proactive. He invites them in and tries to entice them to take a more proactive role as an audience, to try to understand the character and live in their shoes. And I think that’s what makes Decision to Leave so different from director Park’s other amazing films.

AD: Has there been a particular theme from Decision to Leave that has resonated with you personally? Or something that you hope resonates with the audience?

PH: The way I approach any kind of film is that I leave it up to the audience for them to have their own autonomy on what they want to take away, what kind of emotion they to take away from this, what kind of lesson. I try to leave it up to them.

But I think with Decision to Leave, specifically, after I finished filming, I found myself having a difficult time trying to distance myself from the character. There were a lot of residual emotions, and it was, for the lack of a better word,  a bit depressing. And a lot of emotional residue was left with me as a person, even as I was done acting as Hae-Joon. That might be because of the specific character I played, or it might be the indescribable energy that this film has. But, I honestly don’t think I can tell you exactly why it was the case.

I hope this film can resonate with our audience. Hopefully, they can come away with the feeling that it’s okay to be imperfect. Everyone goes through difficulties in life, and not everything has to be a happy ending. I hope that this film can let them know that things can get better. Not everything needs to be wrapped up with a bow on top because, as humans, we operate with our emotions, and that can be messy at times.