True Detective: Night Countryis diving into cold and treacherous territory. Set in the fictional town of Ennis, Alaska, its core mystery centers around the strange disappearance of eight researchers from the Tsalal Arctic Research Station, located 150 miles north of the Arctic Circle. In episode 2, their fates are uncovered, and with them, a haunting parallel to a real-life horror.

In an interview with Vanity Fair, director and writer Issa López professed drawing inspiration from historical events for this supernatural season, including the case of the Mary Celesteand the Dyatlov Pass incident. Lopez has been haunted by these incredibly creepy real-life events since she was a child — and with good reason.

Let's dive into the Dyatlov Pass, so you can be haunted as well. 

What was the Dyatlov Pass incident? 

Between Feb. 1 and 2, 1959, nine Russian hikers died mysteriously while camping in the Ural mountains. The hikers, led by Igor Dyatlov, were on a skiing expedition when the weather forced them to camp on the slope of Kholat Syakhl mountain rather than in the forest below.

Dyatlov was expected to send a telegram to the hikers' sports club when the team returned to Vizhai, the tiny village from which they'd launched their expedition. By the time Feb. 20 rolled around with no word from Dyatlov or the other hikers, their loved ones began to panic and — quite understandably — demanded a rescue operation. 

What became of the Dyatlov Pass hikers? 

On Feb. 26, 1959, the search party found the hikers' tent — and a flabbergasting scene. As described by Mikhail Sharavin, the student who first came upon the site, "We discovered that the tent was half torn down and covered with snow. It was empty, and all the group’s belongings and shoes had been left behind." 

Over a mile away, searchers found the bodies of two of the hikers, Georgy Krivonischenko and Yuri Doroshenko. A few days later, the bodies of Igor Dyatlov, Rustem Slobodin, and Zinaida Kolmogorova were found. But it wouldn't be until the snow melted that the bodies of the last four hikers were discovered. 

Investigators were stymied by the evidence left behind. The tent had been cut open from the inside, and there were footprints in the snow belonging to eight or nine people who were wearing only socks, or one shoe, or were barefoot. 

The condition of the bodieswas even more mystifying, details of which are replicated in True Detective: Night Country. Krivonischenko and Doroshenko were found wearing only underwear. This detail is consistent with paradoxical undressing, a theory proposed in Night Country that might explain why the missing scientists are found naked in the ice. Paradoxical undressing is the phase in fatal hypothermia when victims suddenly feel hot and remove their clothing. 

While medical examiners considered their causes of deathto be hypothermia, certain puzzling details could not be ignored: pulmonary edema and a pulmonary contusion, bruises, third-degree burns, evidence of vomiting blood, and having bitten off a piece of one's own knuckle. Rustem Slobodin's autopsy revealed skull trauma suggesting that he had been forcefully hit in the head. 

The bodies of Lyudmila Dubinina, Aleksander Kolevatov, Nikolay Thibeaux-Brignolle, and Semyon Zolotaryov were found several months later. Their autopsies were performed on May 9, 1959. Ludmila Dubinina was missing both her eyeballs, her tongue, and part of her lips. Plus, there was radiation present on the clothes she was wearing, a sweater and pants belonging to Krivonischenko. Semyon Zolotaryov was also missing his eyes, and he had an open wound on the right side of his skull, as well as broken ribs. Aleksander Kolevatov was found with a deformed neck, an open wound behind his ear, and missing eyebrows, and his skin had a grey-green color tinged with purple. Nikolay Thibeaux-Brignolle had multiple skull fractures, as well as bruises and a hemorrhage on his forearm.

By the end of February 1959, the criminal investigation opened by Soviet authorities concluded that“the cause of their demise was an overwhelming force which the hikers were not able to overcome.” 

What are the theories about what happened at the Dyaltov Pass? 

The grim circumstances of the Dyatlov Pass Incident, in particular the mutilation of the bodies and bizarre details,have produced an army of websites, forums, and academic articles (as well as podcast episodes of Morbid, You're Wrong About, and Atlas Obscura,  and documentaries like An Unknown Compelling Force) offering theories about what might have really happened on that mountain back in 1959. 

Here are a few of the most fascinating. 

Did a yeti kill the Dyatlov Pass hikers? 

One of the most sensational theories on how the hikers met their gory fate involves a yeti. This hairy, muscular beast of legend is said to weigh up to 400 pounds and is also known as the Menkby the Mansi, the First Nations people living in the area where Dyatlov and his comrades disappeared. 

Evidence in this theory begins with Dr. Boris Vozrozhdenny's findings after observing the corpses, declaring that the injuries to the bodies could not have been inflicted by a human being. Further fueling this theory is a photo of a mysterious figurefound on Thibeaux-Brignolle's camera. Speculation "that the yeti lives in the Northern Urals, near Mount Otorten," was published in a parody newspaper created by the hikers, but has also been cited in supporting the theory that a yeti is responsible for their gruesome injuries. 

Did infrasound chase the hikers from their tent? 

Infrasoundis noise that's below the range of human hearing. It's generated by earthquakes and avalanches, as well as sonic booms, ships, and wind turbines. Depending on how intense the infrasound is, it can causedizziness, blurred vision, and fear, and has been linked to paranormal experiences, such as ghost sightings.

In the case of those in the Dyatlov Pass, a wind phenomenon known as a Karman vortex streetmay have produced infrasound, resulting in an irrational terror in the hikers that could have made them flee into the freezing cold. While the infrasound theory seems like a logical one, the tent would have had to be directly downwind from the mountain and far enough away from the winds that it wouldn't be blown over for the sound to have the desired effect. 

What about the unexplained lights? 

Curious testimony was given by Yury Yakimov, a shift foreman working in the city of Severouralsk, 110 miles from the Dyatlov Pass, on Sept. 11, 2002. He reported seeing lights in the sky, as well as a phenomenon that he described as "if several people with strong torches were moving through the thick forest trying to spot me. Unintentionally, I looked away again and froze. Immediately, the torches left me alone. There was something very strange going on…It was something different, very strange and unusual. I realized that I had witnessed an amazing and unusual phenomenon." 

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Later, leaving the site, Yakimov "couldn’t get rid of the feeling of anxiety and danger that I felt as a result of the strange light." Was something extraterrestrial responding to Yakimov that night in September? And was it connected to the fates of the Dyatlov students on their trek decades before? 

Were UFOs and/or Soviet military weapons responsible?  

The idea that a UFOcaused the death of the hikers is one that gained tractionin 1990, when Lev Ivanov, who led the initial investigation of the Dyatlov Pass incident, published an article announcing that his findings had been censored and that, "based on evidence gathered, the role of UFOs in this tragedy was quite obvious." 

This evidence includes unusual char marks on the trees near where the hikers' bodies were found, as well as sketches of flying spheres made by the Mansi people, suggesting something unexplained lurked in their skies. Then there were the mysterious photos of spheres found on Semyon Zolotaryov's camera, which was found intact on his body despite being underwater in a creek for three months. Some propose that the spheres in question were from experimental Soviet weapons, and the char marks caused by heat rays that may have been aimed at the hikers, culminating in panic that drove them from their tent. 

The camera spurs new questions: If Semyon was chased from the tent, why did he bring the camera with him?  And if there were attackers, why didn't they take the camera before abandoning the body? Perhaps the answers make the most sense when we consider the latest developments in the investigation of what happened at Dyatlov Pass. 

What's the most likely explanation of what happened to the Dyaltov Pass hikers? 

The mystery of the Dyaltov Pass has inspired much speculation and theories, including methanol poisoning, a snowmobile,a Russian gulag, and even a time vortex. The most widely accepted theory is that of the slab avalanche.

In 2021, Swiss researchers from the Federal Institutes of Technology published calculations supporting a pre-existing theory that an avalanche was the cause of the deaths of the hikers. The theory was met with skepticism by Russians. But in 2022, a team led by Swiss scientist Alexander Puzrin refuted the criticisms of the Russians, with evidence that there was a risk of avalanche on the night the hikers camped on the Pass. 

A combination of the mountain winds, the loosening of the slope on account of the tent installation, and the unique topography of the area caused the most dangerous type of avalanche. Some of the hikers would have been severely injured by the avalanche (perhaps the strange force mentioned earlier), and others died of hypothermia while trying to escape, which may explain the paradoxical undressing. The injuries incurred to the faces of other hikers were likely caused by scavenging animals. (Perhaps even a polar bear?)

For some, however, this theory doesn't satisfy all the lingering questions. Which is why the Dyaltov Pass incident continues to haunt our imaginations. How will this real-life incident — and the many theories around its cause — impact True Detective: Night Country? We'll have to keep tuning in to uncover the truth. 

True Detective airs Sunday nights on HBO/Max at 9 p.m ET/PT.