Allow me to say something a little counter-intuitive here. Don't read this. Just trust me and watch Into the Deep when it debuts on Netflix later this year. Not enough? Fine, but don't say I didn't warn you.

Into the Deep isn't just a documentary about the Danish inventor Peter Madsen, it's about the unexpected turn into murder that happened while the documentary was being made. Additionally, the presence of Australian director Emma Sullivan's cameras is able to draw out a response from a group of people that may not have happened on its own. It's fascinating and I've never quite seen anything like it.

Up until summer 2017, Peter Madsen was a local celebrity in Copenhagen. Part genius, part kook, the very camera-ready engineer and futurist made his living giving public talks, then poured his resources (and sponsorships) into building rockets and submarines. Think of him as something of a very micro version of Elon Musk. (They even kinda look alike.)

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He assembled a group of admirers in what looked to outsiders like a benign, crafty cult. There was a degree of hanky-panky with some of the young women in the group, but everything seemed out in the open. These were freethinkers hanging out in an abandoned warehouse measuring g-forces and jet propulsion.

A guy like this is certainly going to draw attention, so documentarian Sullivan got herself to the compound near a Danish canal and started shooting. Additionally, a journalist named Kim Wall, on assignment for Wired magazine, came by for an interview. Madsen took her for a dive in the Nautilus, his hand-made sub, then the two disappeared.

That's where the movie starts, with the gang worried sick about him, but later he's found near the Swedish border; his sub has sunk. Kim Wall, he claims, got off the boat earlier, but then no one can find her. Her boyfriend says she's missing. And then body parts get found in the water.

Into the Deep jumps back and forth between before the disappearance and after, expanding the timeline and capturing a number of extraordinary things. The more flashy and disturbing side of this film — and the one that will give us all nightmares — is seeing how psychopaths preparing for a thrill kill are, in fact, living among us. Madsen isn't just a functioning adult, he is a capable leader and is terrific with people. We'll later learn that just a few minutes before a cheery on-air interview he was on his laptop watching brutal execution videos from the dark web.

Into the DeepInto the Deep

The secondary aspect of Into the Deep dawns on you more slowly, which is appropriate as it is all about Madsen's posse becoming aware that they were in a cult leader's grip. The longer he stays in prison awaiting his trial, the more his hold over them dissipates. Maybe he wasn't such a genius, they think. Maybe we would have been better off not spending all our spare time working on his bizarre projects. Worst of all, maybe we inadvertently assisted in the rape, torture, and brutal dismemberment of Kim Wall by making all of Peter Madsen's dreams come true.

Watching Madsen's small group of associates (most of them quite young) wake up is like a barbarous version of The Truman Show. They are not to blame, but once they realize what the man they admired was all about, they all take the eventual step to condemn him.

Emma Sullivan is brilliantly selective with how she metes out the footage. Early in the film, Madsen is a charming, mad genius. Who wouldn't want to fire rockets with him? Toward the end, we see just how premeditated and how meaningless Kim Wall's murder was.

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Madsen had nothing against Wall, he simply had it in his head that he had to kill a woman — it was a goal, like climbing a mountain, or building a sub — and he thought he was smart enough to get away with it. It's heartbreaking and terrifying when the other women in the group realize that had Wall not popped by for an interview, it would have been one of them.

I left Into the Deep in a daze, not knowing how to apply its lessons to everyday life. I suppose that if I ever meet someone who makes multiple jokes about beheading people, I'm getting the hell out of there.

This film is far greater than the typical true crime Netflix documentary (or one of the myriad podcasts out there) because it isn't about the subject, it is the subject. Footage eventually used in Into the Deep was submitted as evidence in Peter Madsen's trial. That's still not going to help me get to sleep tonight.

Editor's note: Before the film premiered at Sundance, its cinematographer, Cam Matheson, disavowed the film, and a woman, Anja Olsen, who appears in the movie, says she did not give her consent to be featured in the film.

TV Guide Rating: 5/5

Into the Deep was screened at Sundance. It comes to Netflix later this year.