Nearly four years after the assassination of Kim Jong Nam, the estranged half-brother of North Korea’s leader, a new documentary seeks to lift the curtain on the brazen murder and the involvement of the two young women accused of carrying it out.

Kim’s killing at klia2 in February 2017 was caught on grainy CCTV footage broadcast around the world, yet to date, many details remain a mystery.

US director Ryan White spent two-and-a-half years delving into the case for “Assassins”, which will be released in cinemas and digitally on demand today.

At the centre of the film are the two women – Indonesian Siti Aisyah and Vietnamese Doan Thi Huong – who were charged with poisoning Kim by smearing his face with a banned chemical weapon and faced a mandatory death penalty in Malaysia.

Defence lawyers maintained the women were pawns in an assassination orchestrated by North Korean agents. The women said they thought they were part of a reality prank show and did not know they were poisoning Kim.

South Korean and US officials have said the North Korean regime had ordered the assassination of Kim, who had been critical of his family’s dynastic rule. Pyongyang has denied the allegation.

For “Assassins”, White combed through the pixelated CCTV footage and examined evidence presented in and out of court. He attended the court hearings, interviewed defence lawyers and family members, travelled to Vietnam and Indonesia and filmed in central Hanoi and Kuala Lumpur’s red light districts to tell Doan and Aisyah’s backstories.

But it was hearing from the women themselves that he considered most crucial in order to shed light on the case.

“The women were understandably wary of us because they had just almost faced the ultimate penalty, their lives, for having fallen for a film crew saying that they were going to make them famous. And suddenly I’m coming along saying the same thing to a certain extent. So it took a while with both of them to convince them that they could trust us,” he said.

In a case full of twists and turns, the women, too, took White by surprise. Doan, who had been seeking fame for over a decade, turned out to be shy and reserved and reticent to take part in the film, White said, while Aisyah bubbled with enthusiasm.

“I think it was a very big lesson, and I think what’s behind our film, which is the idea of like, you know, when you look at the headlines, you might infer one thing, but when you pull back the curtain, it could be completely something else. And even the image that I had built up in my own head of the two women was that way as well,” he said.

Doan and Aisyah were shown the documentary earlier this week and while the film received their blessing, Doan expressed regret over some scenes, White said.

“Her first reaction to the film was, I wish I hadn’t smiled so much,” said White, referring to scenes showing Doan’s return to Vietnam.

“It’s been over a year since they’ve been released, she’s really experienced the vitriol and sort of meanness of the world of social media outside judging her for having fallen for this. And so she’s retreated into her shell a lot more. So it’s sad to watch her that that was her first reaction, like saying, I wish I hadn’t smiled so much when I was released,” he said.

“They’re both lovely and thankfully survived this experience, but I think their lives will never be the same, unfortunately.”