On the evening of August 10, 2017, 30-year-old Swedish journalist Kim Wall disappeared while interviewing the Danish inventor Peter Madsen on board his homemade submarine, UC3 Nautilus – a vessel that had turned him into a minor celebrity in his native Copenhagen. Wall was writing a piece about the eccentric, media-friendly Madsen for Wired magazine, as he was now attempting to become the world's first amateur astronaut by building his own space rocket.
When Wall had not come home or been in contact by 1.45am, her boyfriend called the police. By 10.30am on August 11, the submarine was located by the Danish navy. Shortly afterwards, it sank. After being rescued – alone – Madsen at first maintained that he had delivered Wall to dry land the previous night. He was immediately charged with her murder and quickly changed his story: she had died on board in a mishap, he claimed, when he accidentally dropped the submarine hatch on her head, and he had buried her at sea, as was the maritime tradition.
Eleven days later, Wall's torso was found by a cyclist, washed up on a beach in Koge Bay, south of Copenhagen, close to where Madsen and the Nautilus had been rescued. It had been stabbed 15 times and weighted down with metal to ensure it sank. Soon afterwards, Madsen's computer hard drive was discovered containing graphic videos of women being tortured and decapitated.
Two months later, in early October, police divers recovered a bag containing Wall's shirt, skirt, socks and shoes, then, shortly afterwards, one leg, then another leg. They next found her head, lying at the bottom of the sea in a bag that had again been weighted down with several pieces of metal, and in November they located her arms.
There was no sign of any fracture or of any blunt trauma to the skull, and Madsen's long-held explanation – that Wall had hit her head and he had disposed of her body – crumbled.
The bizarre and macabre murder, along with its lengthy investigation and trial, has already spawned several documentaries as well as an acclaimed HBO drama, The Investigation, notable for Madsen never appearing on screen nor even being mentioned by name.
Emma Sullivan's documentary, Into the Deep, released this week on Netflix, is a different proposition – not least because Madsen features prominently in extensive, intimate contemporaneous footage. The Australian film-maker had been following Madsen for more than a year before Wall's murder, interviewing him and the team of engineers and volunteers who worked on his space programme. When Wall disappeared, Sullivan kept filming.
"This was not the film that I wanted to make," she says. "But when the story changed significantly, I don't think that my approach to the film changed."
What unfolds over the course of 90 minutes is the journey of Madsen's friends and colleagues – and of Sullivan herself – from disbelief to shock to bewilderment, as the brutal actions of a man they have not only worked alongside but idolised become apparent.
There is Stefan, a young, wide-eyed engineering intern who had seen Madsen on television and YouTube and moved to Copenhagen to work with him. He "wanted to be like this guy", who "with a mixture of a dream and craziness" was "doing something completely new".
There's Sara, a volunteer at RML – Raketmadens Rumlaboratorium, Madsen's space lab – who talks of the two of them "understanding each other's emotions and passions. He knows how to pick me up from where I am… He knows how to tell me I am great as I am."
And there's Christoffer Meyer, the no-nonsense RML flight director, Madsen's lieutenant for a decade. "He was part of my inner circle. This is a person that I utterly trusted," he says.
Today, we're in a slick office at Netflix's London HQ. Sullivan is thoughtful, incisive, articulate, but also clearly still deeply affected by her experiences.
She prefaces what she's about to tell me with a warning. "I'll get teary sometimes – don't get too bothered by it. It's a physical expression that I don't have much control over," she says, already wearily wiping away tears.
"It's been five years, but I still get emotional," she continues. "It's a trauma. Intellectually I'm OK, but there's always a rumbling inside. I've got many more tears to shed about what happened, because it deserves them."
There's also a second, equally important caveat. "Everything I say today, it's with Kim and her family in mind," she stresses. "And [that's why] it's really difficult for us on this side of the story to express ourselves." She'd go so far as to say that her perspective is "a taboo. We don't feel worthy of attention. I think a lot of people who go through the experience of being close to a perpetrator hide in the shadows and have deep feelings of guilt and shame and complicity."
But, she says, "reams and reams of papers have been written about psychopaths. Far less has been written about those who have lost somebody [to a psychopath]. There's next to nothing written about this experience."
There's a quote that she says she has found helpful from Robert Hare, who created the psychopathy checklist in the Seventies. "I'm paraphrasing, but he says that those who have been exposed to a psychopath are extremely vulnerable. They really struggle with self-doubt and shame and guilt and complicity. It's so difficult to know how to find help. And on top of that, you don't even feel worthy of it.
"And I don't think that this type of horrific event has been captured in quite this way before," she says of documenting it all. "We're encountering this experience through those that found themselves on the wrong side of the story – people who were there for something good and instead were dragged through something horrific. I think it demonstrates that the ripple of emotion and pain that goes through a society when murders happen is far-reaching."
Born and raised in Brisbane, 45-year-old Sullivan was living in Aarhus, Denmark, when she came across the charismatic Madsen via his frequent television appearances and his TED Talk. She wrote to ask if she could film him as he embarked upon his somewhat improbable space programme, in which he planned to build a rocket in a disused shipyard and launch himself into space from the middle of the Baltic Sea.
Madsen invited her to the lab on Refshaleoen island in Copenhagen, a former industrial area now home to artists and musicians who populated the old warehouses. The lab, says Sullivan, "was filled with young enthusiasts and some really gifted engineering interns". Everyone dressed in military fatigues and flight suits. "He wanted everyone to wear the uniform and they did it for a bit of fun. These people were doing master's degrees in astrophysics and engineering, and at the lab they could climb over a submarine and play with space rockets and a centrifuge. It was a really joyous place, full of a lot of laughter and fun and experimentation."
Madsen was, she says, "charismatic, singular, and a lot can hide with that sort of person at the helm". Looking back, there were red flags. Madsen frequently "joked" about machine guns and murder, made idle but graphically violent threats, and the day before Wall's disappearance, asked Stefan if he knew the name of the website where he could view victims of murders.
In the lab, Madsen was well known to enjoy BDSM and fetish parties, and to have a less than conventional romantic life. Though he was married, he had many other girlfriends. "If they had agreed on that and they could make it work? Fine," says Meyer, when I speak to him on the phone from his home near Copenhagen. "It's not the relationship that I have with my wife, for sure, but it's not for me to judge. It wasn't a secret in any way – everybody knew about it."
"For most of the first year that I was there, I hadn't been introduced to that side of him at all," says Sullivan. "I understood that he had an open marriage, but that's not that unusual these days. But in early 2017, he started to become more open with me about that aspect of himself, and that he was interested in sex clubs and BDSM clubs."
He never tried anything directly sexual with her, she says. "Any time that he tried to make a flip remark or became a little bit flirty I was really quick to cut it out. It's not the first time in a work environment that I've had to shut something down, and I did so very firmly."
However, she says – perhaps with an instinct honed from years of interviewing and observing – she began to feel there was something less than straightforward about Madsen. She has what she calls a "one-sheet" when making a film – basic questions about everyone she is documenting – which she runs through periodically with herself. "What are they concerned with? What are their goals? Things like that. And one of them is, 'Do I believe them?' I would always write with Peter Madsen, 'Yes.' But there was a certain point when I read that question and my answer was, clearly, no.
"I'd been around long enough to understand that he was a narcissistic person and that he was out for his own self-interests," she says. She began to worry that the much anticipated rocket launch would not be a success. "I began to feel a little concerned that he wouldn't land the parachute, and all these people who really care about him will be left behind."
On the morning of Friday, August 11, 2017, when she learnt – via a frantic stream of text messages and phone calls – that Madsen and the submarine were missing, "I remember thinking, 'Well, this is it. This is how it ends. This is how he goes and this is how everyone's left.' "
By midday, conflicting reports were rushing in. "He's alone. No, he's with two journalists. No, he's with one journalist. The journalist is male. No, it's one female. When we realised it was one female journalist, I did feel more concerned," she says. Sullivan's lower set of teeth chatter involuntarily at this memory. When Madsen was rescued alone, "I do remember saying, 'I'm very worried,' because when two people go out and the woman disappears, when is it ever a good story? It became very clear that something terrible had happened." Meanwhile, she says, "The people who were close to him were trying just to hold on to any other reality than reality itself."
While it makes for compelling storytelling, witnessing their disbelief slowly – and then more quickly – morph into horrified acceptance, were there not moments, I ask Sullivan, when she felt she should stop filming? Yes, she says – on the day that the first of Wall's remains were found. "I needed to have a really deep think about why we should continue. But I think the answer at the end of that was that it's a very important story to tell."
That day was also, she says, "a point of no return. There's no good news from there. A lot of hope disappeared on that day. And there was a lot of grieving for someone we didn't know."
At the lab, horrifying realities hit home as those days and weeks unfolded. For Sara, there was the growing realisation that it could easily have been her aboard the submarine that evening; Madsen had invited her, as well as Sullivan and several others in the days leading up to Wall's death. In their verdict, the court said it was "a premeditated murder of a woman, not a premeditated murder of Kim Wall".
For Meyer, "It made me physically sick. He was my friend. I started to feel a certain sense of shame. And you do start feeling guilty. Because had I known that he would have been able or capable of doing this, I would have done everything I could in my power to stop him.
"You really start questioning yourself, and the belief that you have in other people," he continues.
Meyer works in sales these days. "A salesperson's toolbox is to read people – that's what we do professionally. So it really hit me, and I really questioned my ability to read people and, from a social point of view, to interact with others."
For Sullivan, not only was she documenting the unravelling of a community and its collective realisation of what their friend and leader was capable of, but there was also a growing awareness that her own year-plus worth of footage might be valuable. Footage, for example, in which Madsen discusses the possibility that he might be a psychopath. And footage from the morning of August 10 in which he had gone off on a tangent ("That wasn't unusual, to go off on such tangents") about being in a courtroom – "And if you are saying, yes, I was in the process of murdering my neighbour's wife… If you are under siege, accused, you shouldn't say anything. I have the right to remain silent." Seven months later, in court in Copenhagen, pleading not guilty to Wall's murder, he would say, "I am holding back my explanation until your evidence means I have to tell you what death she suffered. How she died. Until you can prove what happened."
One of the problems was that the investigators couldn't. There was no cause of death that could be ascertained and no forensic evidence to disprove Madsen's version of events that she had died onboard. (He did admit to dismembering her body, but said in court that he "didn't see how it mattered, because she was already dead".)
"We realised that we were witnesses, that we could assist the police in their investigation and the prosecution in the conviction," says Sullivan.
Ten witnesses from the space lab gave evidence, including Sara, whose text exchanges with Madsen in which he described a fantasy of murdering her aboard the Nautilus were also submitted. In its ruling, the court stated that footage taken by Sullivan and used in Into the Deep proved instrumental in his conviction. "As difficult as the details are of this particular murder and as damning as that seems, on that day of the verdict, even the prosecutor himself couldn't have been sure of the verdict," says Sullivan. "The fact is that there was no cause of death and there was no concrete evidence. It was purely a huge volume of circumstantial evidence that got him convicted."
The guilty verdict, when it came, and the sentence of life imprisonment may have been widely applauded, but the trial itself posed questions about the coverage of such crimes. Much of the reporting was lurid and sensational, focusing on the grisly details of Wall's death and Madsen's sexual peccadilloes, while representatives of several media outlets live-blogged from the courtroom. "It really played out like a courtroom drama," says Sullivan.
In wider coverage there was victim-blaming, questioning why a female journalist would ever board a stranger's submarine alone. "It was heartbreaking and infuriating at times, especially this commentary that somehow she hadn't done due diligence," says Sullivan. "He was a semi-celebrity, and if you hadn't been on the submarine yourself you at least knew someone who knew someone who had. And it was absolutely not unusual that he would take journalists on the submarine – there had been many journalists from all around the world on that thing. There was no reason for her whatsoever to be alarmed."
Into the Deep premiered at the Sundance Film Festival in early 2020. However, so traumatised were two of the people in it that they withdrew their participation following the premiere, forcing the film to be heavily recut.
Several of the remaining interviewees have had their voices altered to protect their identity and, using cutting-edge technology, Sara's physical image has been digitally altered for her protection too. "She, like everyone else in the film, feels vulnerable," says Sullivan.
"She says, 'There were signs that I didn't notice,' and I think that is something that still haunts so many people. This is beyond people's reasonable experience and expectations, and so those that were close to him – and more generally those who have encountered dangerous personality types – do end up with these feelings of, 'What is wrong with me? What did I miss? How could I have stopped this from happening?' The tragedy in all those thoughts is they're futile, because you can't."
It took Sullivan years to find a therapist who could help her unpack all this. She called around in several English-speaking countries. "I said, 'This is the experience that I've had. I've been near this particular person and I'm looking for assistance. I'm looking for ways through this.' "
There were, she says, lots of victim centres and violent crime centres and places to help families of the deceased. "And as wonderful as they were, and as helpful as they wanted to be, there was no formal support for those that have experienced a psychopath.
"It's affected my life profoundly," she says. "It's made the world a slightly darker place. That there's a talented female journalist, Kim Wall, who's not alive today because somebody that I knew brutally took her life – it's still hard to digest.
"It's not to say that I can't have wonderful days and enjoy my life, but there is a tiny hint of darkness that I will always carry."
• Into the Deep is streaming on Netflix from Friday
Written by: Jane Mulkerrins
© The Times of London