Park Chan-wook invented Decision to Leave 's tragic ending decades ago

Warning: This article contains spoilers for Decision to Leave.

Filmmaker Park Chan-wook crafted the devastating ending of Decision to Leave, his newest film (out today), decades before he became a director.

In the romance mystery, Park Hae-il and Tang Wei play doomed love interests, a detective and his murder suspect, drawn to each other despite the circumstances. Layered with the Oldboy director's signature twists, the noir concludes with the suicide of Tang's Seo-rae — one aided by the sea, and a callback to detective Hae-joon's (Park) instructions to dispose of her dead husband's smartphone in the ocean. She digs a hole in the sand, crawls in, and waits for the tides to wash over the opening. When a frantic Hae-joon arrives, traces of the hole, and Seo-rae, are gone.

Mubi Tang Wei and Park Hae-il in 'Decision to Leave'

The ending goes back to an idea Park had for a short film over 30 years ago: "There's this man, and he digs a hole and he goes inside," he tells EW. "And using complex machinery [and] the entire patch of ground, including the grass and the soil, it goes over his little hole as if you're covering a lid. And it looks like nothing happened. He leaves no trace of himself and basically evaporates from the world. The story doesn't really explain why he committed this particular form of suicide. I never got to film this story. I forgot about that idea for a while."

When it came time to write the ending for Decision to Leave, Park revisited the decades-old idea. "Seo-rae must forever remain an unresolved case to Hae-joon," the filmmaker adds. "Seo-rae wanted Hae-joon to spend sleepless nights looking at a photo of her and thinking about her. This might come off as a cruel kind of emotion, but this was her emotion. So she has to find a way where she can disappear without a trace."

Mubi Tang Wei in 'Decision to Leave'

"As she is an ocean person," Park continues, "it would be even better if she uses the power of the ocean to achieve this goal. Unlike hanging herself or shooting herself, it's not an active form of suicide where she uses her own power. We are borrowing the power of the ocean. It's also a method of patience — a method of waiting and accepting one's fate."

An epilogue that featured a "completely destroyed" Hae-joon, wherein he loses his job as a policeman, almost made the film before Park determined that he was already "forever cursed" come the closing credits, unable to tell if his love is alive or dead or simply missing, Park says.

Just don't interpret that devastating finish as a sacrifice. "I don't want the audience to think that Seo-rae sacrificed herself to prevent a man from ruining his career or his marriage, that she disappeared for the man," Park says. "Instead, she has chosen a personal way for herself, and this is her method of liberation and to attain freedom for herself. That's how I want the audience to think of the ending."

Related content:

• Murder begets romance in Oldboy director Park Chan-wook's latest thriller Decision to Leave

• The Handmaiden: 5 movies that influenced Park Chan-wook's thrilling, erotic mystery

• Loved Parasite? Here are more great South Korean films to watch