The disturbing story behind Netflix's true crime documentary Into the Deep.

On August 10, 2017, Swedish freelance journalist Kim Wall received a text. It was from a source she hadn't heard from in months. That afternoon she was on her way to meet Danish inventor Peter Madsen. 

Wall and her partner had their going away party happening that evening, in farewell to the pair who were moving from Copenhagen to Beijing, but the opportunity to speak with Madsen and ride on his incredible self-made submarine was too good an opportunity to miss.

Watch the trailer for Netflix's Into The Deep. Story continues after video. 

The ride on the submarine was supposed to last two hours, from 7pm to 9pm. When she hadn't come home by 1:45am and her family and friends hadn't heard from her, her boyfriend called the police. 

The next morning could be described as somewhat of a blur, but it is heavily documented by Danish authorities, media and documentarians. 

By 10.45am that day, the sunken submarine was located by the Danish navy. There were initial concerns that Madsen and Wall had perished on the submarine after becoming trapped, but Madsen was later located and rescued.

Wall was nowhere to be found. 

My friend Kim Wall has gone missing on Friday in Copenhagen. If you have any info please contact Danish police. https://t.co/SUv0N3JjHY pic.twitter.com/3e9ScqX6W4

— Marie Telling (@MarieTelling) August 11, 2017

Madsen told police he had dropped Wall off on shore the previous evening but they did not believe him. He was arrested and charged with involuntary manslaughter.

Madsen's story changed overnight. He told investigators he had never dropped her off on land but instead carried her body from out of the submarine and "buried her at sea". He had done this, he said, after a hatch had fallen on her head. She had died on board. 

Kim Wall. Image: Getty.

Madsen's story developed into something completely different once again, when on August 21, a torso belonging to the investigative journalist washed up near where the submarine had sunk. 

He claimed that a technical malfunction had occurred and that Wall had died from carbon monoxide poisoning. To carry her body out, he made the job easier for himself by dismembering her body. 

His charge was changed to manslaughter and over the coming months, the investigation team worked tirelessly with diving and search teams to yield Wall's head, arms, legs, clothing and a saw from the water. 

Madsen's lies wouldn't mean much in the end when videos of women being decapitated, impaled, and tortured were found on a hard drive owned, by the police. 

Into The Deep. Image: Netflix.

A woman that the inventor had a sexual relationship with turned over texts in which he admitted to planning out a crime where he would cut a woman up on his submarine. 

Police also found a web search. Some of the terms were "beheading," "girl," and "agony". These searches were made on August 9, 2017, the night before Wall was murdered. 

On January 16, 2018, a new indictment for Madsen was released. He was charged with a homicide that "took place with prior planning and preparation" as well as "sexual relations other than intercourse of a particularly dangerous nature, as well as for dismemberment."

In his 2018 trial, he was erratic. He switched between speaking about himself in the third and first person, his accounts changed from present to past tense. He made endless movie references and even went as far as to apologise for his horrific acts "sounding like a bad movie."

When asked why he lied so many times about his crimes, Madsen said he wanted to "protect" Wall’s parents from the truth of her "gruesome" death. 

He said watching violent pornography and acts on his computer made his "empathy" come out and that it gave him the tendency to "always root for the underdog."

By the end of his trial, he was sentenced to life in prison and made to pay $19,700 USD to Wall’s boyfriend. His submarine was also ordered to be destroyed. 

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Madsen would make headlines a few more times following his sentencing. In October 2020, he escaped from Herstedvester Prison - where he was sent to carry out his lifelong prison time. 

On him, he wore a fake bomb that was attached to his chest and was seen carrying an object that resembled a gun. Madsen was captured a little more than a kilometre from Herstedvester. 

There have been other times when his name has been mentioned in news, too - and it's been as a result of documentaries, books and reports looking to cover the case. 

A true crime series was pulled after it received a heap of criticism for attempting to sell Wall's horrific murder as "entertainment".

Netflix also pulled the documentary Into The Deep from its 2020 lineup for having the ability to re-traumitise people who didn't consent. Two individuals protested against the film.

As a result, the participants were removed from the film and another was "digitally disguised".

Into The Deep. Image: Netflix.

The documentary launched on Netflix in 2022 and tells the story of the horrific events that occurred in 2017. However, the story begins a year prior, in 2016, when Australian filmmaker Emma Sullivan began to document the life and work of Madsen. 

Into the Deep is compelling viewing because it shows Madsen's colleagues struggling to comprehend how their mentor and "friend" could commit such a horrific crime. The footage switches between past and present, and the interviews with Madsen are chilling once viewed in retrospect.

There is one particular scene that helped convict Madsen - the wall behind him in the footage shows a saw with an orange handle hanging up, and then later on, the saw is no longer there. Madsen had taken it on board the submarine before meeting Wall, showing that he had planned her murder in advance.

"This is a very personal story to me. When I started this project, I met a group of people, who wanted to be part of something positive with someone they admired at the helm," filmmaker Sullivan said.

"But then the unbearable happened. When you are suddenly pulled into such a nightmare, it changes your life forever.

"The film is a testimony of the people who were close to Madsen as they slowly grasp the true nature of the man and the terrible crimes he committed."

Donate to Kim Wall's memorial fund here.

Feature Image: Netflix/Twitter.