The terrifying real-life serial killer who inspired Bong Joon-ho's first hit movie.

For five years, the residents of Hwaseong in South Korea lived in fear. Someone was raping and murdering women, from teenagers to the elderly.

Women walking alone were most often targeted, and they were usually tied up and strangled with their own clothing. Some of the women’s bodies were mutilated.

Police investigated 21,000 suspects without finding the man responsible for the crimes. He became known as the Korean Zodiac Killer.

A 71-year-old grandmother, Lee Wan-im, was the killer’s first victim. Her body was found in a field in September 1986. She had been returning home from visiting her daughter. Other victims were attacked while walking home from the bus stop. Some were high school students. One woman was killed while going to give her husband an umbrella. Over the course of five years, 10 women’s bodies were found.

The youngest victim was just 14. Park Sang-hee was the only one murdered in her own home.

In 1989, police arrested a man, Yoon Sang-Yeo, for the murder of Park. Yoon was a young, uneducated rural worker who couldn’t afford a lawyer. He confessed to the crime and was sentenced to life in prison, but later claimed police had tortured the confession out of him.

Police said the killing of Park was a copycat crime. No one was charged for the other nine murders. The last one was in April 1991.

In the early 2000s, future Oscar winner Bong Joon-ho was a young director with just one feature film to his name when he decided to make a movie based on the Hwaseong killings. He tracked down police officers, journalists and other people involved with the investigation, and spoke to them, face to face.

“The only one who I could not meet was the murderer,” he said.

The director says he became very curious about the murderer and thought a lot about him.

“I wondered what he looks like.”

Bong Joon-ho's 2003 movie, Memories Of Murder, was a hit. Although it was only based loosely on the murders, it included some of the real-life detail. Bong’s career took off. The movie kept the murders in the public consciousness.

South Korea has a statute of limitations on crimes. By 2006, the statute of limitations on the last of the Hwasaeng killings had run out. But police kept investigating.

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In 2019, police finally made a breakthrough. They matched DNA samples taken from a victim’s underwear with a man called Lee Choon-jae. He was already in prison, serving a sentence for murdering his sister-in-law.

Lee was a construction worker who lived in Hwaseong at the time of the killings. In 1986, he’d just returned home after his compulsory military service. He was one of the 21,000 suspects questioned by police over one of the murders, but he was released because of lack of evidence.

In 1991, Lee got married and moved to Cheongju to be closer to his wife’s family. But two years later, his wife left him. In January 1994, he invited his wife’s 18-year-old sister over to the house, and raped and killed her.

After his sister-in-law was reported missing, Lee asked, “How many years do you serve in prison for rape and murder?”

At that point, no one knew she had been raped and murdered. Police found blood in Lee’s bathroom that was determined to belong to his sister-in-law, and he was sentenced to life in prison.

At first, Lee denied any involvement in the Hwaseong killings. But late last year, police announced that he had confessed to all 10 murders, including the murder that Yoon had been imprisoned for. Police said Lee had also confessed to killing five other women – three in Hwaseong, two in Cheongju – and raping or attempting to rape more than 30 more.

“I express my deep condolences to the victims and their families, as well as the Korean public, for not having been able to solve this case for a long time,” senior police investigator Ban Gi-Soo said. “We will do our best to discover the truth with a sense of historical responsibility.”

For Bong Joon-ho, by then promoting his latest movie, Parasite, it was a big moment.

“Finally last week I was able to see a photo of his face,” he told a film festival audience in Los Angeles. “And I think I need more time to really explain my emotions from that, but right now I’d just like the applaud the police force for their endless effort to find the culprit.”

Feature Image: Memories Of Murder/CJ Entertainment