Nikolaj Coster-Waldau had many formidable foes on Game of Thrones as “Kingslayer” Jamie Lannister—from dragons to White Walkers. Of course, those threats didn’t exist outside the lens of the fantasy series, but in Against the Ice, the enemy of his character, real-life explorer Captain Ejnar Mikkelsen, was also an on-set tormenter of the Danish actor. That enemy was the bitter, bitter cold.

“No question this was the hardest shoot I have ever done, but that’s what telling this story required,” says Coster-Waldau. The movie portrays Captain Mikkelsen’s 865-day journey into the Arctic to dispute a claim that the U.S. made on Northeast Greenland. On agreement with director Peter Flinth and producer Baltasar Kormakur, the actor ventured to the Arctic to film with sled dogs and snowstorms. “There’s no way a wind machine and some fake snow was going to do right by the men of that expedition.”

We spoke with Coster-Waldau about the Danish explorer, bear attacks, and having to evacuate set because of a blizzard.

Men’s Journal: Before starting the writing process, how familiar were you with Captain Ejnar Mikkelsen and his expeditions?

Nikolaj Coster-Waldau: I knew his name, and that he was an Arctic explorer who had accomplished some great feats, but nothing beyond that. I didn’t know about the Alabama expedition. The director, Peter Flinth, is a long-time friend of mine, and he sent me a copy of Mikkelsen’s book Two Against the Ice. I was blown away by it. There was the survival story, which is unbelievable in its own right, but also the human relationship story underneath—the camaraderie between these two men who end up spending 865 days together in extreme conditions.

There’s a moment they experienced—it’s in the book—where they had a simple postcard with women on it and they were fantasizing about companionship. Mikkelsen’s traveling partner Iver Iversen picked three of the women on the card to be his “girlfriends” and Mikkelsen picked one. I thought that was a fascinating and beautifully raw moment where they recognized how much they needed love. I knew it would make for a great movie.

What other research did you do?

Mikkelsen wrote two books about the expedition. In the first one, he doesn’t really mention Iversen at all. In the second book, he goes into much more detail about their companionship, and credits Iversen for getting him through the journey. I thought that was also an interesting wrinkle in their tale and something that could be investigated. I read all of Mikkelsen’s books, but I also connected with his family. I chatted with Naja Mikkelsen, who is the great granddaughter of Ejnar. Those conversations were hugely helpful. I had known that Mikkelsen had married his wife a year after he returned from that voyage, but there was no mention of her in the book. We were able to confirm they were seeing each other at that time in secret, and he carried a locket with her photo in it. The dialogue we have between the characters is made up, of course, but the conversations are based in truth.

Were there specific themes you were most intrigued by in the writing process?

There are definitely themes we wanted to explore throughout. They really didn’t know they were going to make it at the end. One of the first scenes we wrote happens toward the end of the movie, where they’re discussing what point they’d resort to cannibalism. The scene always gets a laugh, but that reaction is born out of the discomfort and horror of the situation. The laughs are needed to deal with the uncertainty of their futures. The other element we leaned into was how the mind copes with extreme isolation—how they created these visions that were just as real as their true lives.

The cinematography in the film is stunning. You can sense how brutal the terrain is. Was this the most arduous shoot you’ve done?

These were the most extreme and challenging filming locations I had ever been to, but that’s what we were set on from the very beginning. We wanted the environments we captured on camera to be as authentic to the story as possible. These are places we wanted to be in and share with the audience. My wife is from Greenland and we’ve been going there for years. Every time I go there, I’m in awe. I wanted that feeling to come across in the film as well.

Sure, you can try to recreate those places with computers, but you can’t recreate the effect it has on everything else—and us as actors. That kind of cold affects the way you speak and move. I was ecstatic we were able to work with Baltasar Kormákur, who produced this along with his company RVK Studios in Iceland. Everything you see during these scenes is real because of those efforts.

How difficult was it to get to these locations and get through the shoots?

The longest trek we had to do was two-and-a-half hours on snowmobile when we were filming in Greenland. There’s no way we would’ve made it to the places we needed to go without the Greenlandic crew. I was blown away by the vehicles and machinery necessary to get us to some of these places. There were these crazy trucks and Super Jeeps I had never seen the likes of before. But that’s what we needed to get onto the glaciers. The weather got pretty rough at times, and we filmed as much of it as we could. Out in Greenland, we needed 22 snowmobiles—with three people on each one—to get our crew out to where we needed to film. One of the days we had to shut down and evacuate because of a blizzard.

At what point did you realize you needed to evacuate?

We knew the weather was going to be bad, but they were telling me it was going to get better at lunch. It only seemed to get worse and worse. The snow kept getting heavier and the cameras actually started to shut down because of the cold. Eventually the call came through that we needed to return to base camp immediately. There was a cabin for the rangers who worked there. They needed us to evacuate. As I was walking in, I saw one of the production vans had all of its windows smashed out from flying rocks during the storm. So that gives you an idea of the elements we were dealing with. They had to count heads to make sure we were all there. Everyone on location was given a whistle in case they got lost or fell into a crevasse. That was just par for the course to make sure the crew safely made it home.

Mikkelsen traveled by dog sled during his expedition, and there are a lot of great sledding scenes. What was it like to work with those animals?

First of all, it’s important to note that no animals were hurt in the process of making the movie. I loved those dogs. But they are not pets. You can’t get too close to them without asking their owners and trainers first, because they are not all friendly. They’ll bite you. What they are is good at their jobs. They have profound joy you can sense when they’re pulling the sled together. That’s how they traveled back then and that’s how they still get around in the northwest of Greenland. It’s the most reliable, safest, and fastest way to commute. My wife grew up traveling like that—with dogs. She had her own little sled with five dogs to go over the sea ice. There were kids that would come by the filming locations on their own little sleds with a few dogs. We had to point them in other directions. It’s a beautiful tradition that’s under threat because of climate change. My favorite shot is at the beginning of the movie when we’re going over sea ice with the dogs. Thirty years ago, there were three meters of ice there. Today it’s less than a meter. It’s sad that we may lose these traditions and the places they call home.

Speaking of animals, there’s an epic polar bear attack scene. I know you worked with real bears before, but this was computer generated. It looks incredible.

I have worked with real bears—including Bart the Bear II that we had on Game of Thrones, who sadly passed away last year. For Against the Ice, director Peter Flinth mentioned he’d seen a movie where a bear attack was filmed with a real bear. He thought that it would be easier to get a real one, and went as far as locating a bear in Svalbard that might work. But we ended up going the CGI route—and I’m glad we did, because it looks great. It was probably in my best interest as well.

We still needed something or someone to stand in there and play the bear. We got connected with this Olympic judo champion in Iceland to step in. He was a really strong lad, and basically spent his time tossing me around in the snow. By the time we got to take six or seven, everything was spinning. I told the crew I had to go vomit somewhere. I’m pretty sure I got a concussion.

There are tremendous performances by Joe Cole, as the ship’s mechanic, and Charles Dance, your buddy from Game of Thrones, as Mikkelsen’s disbeliever in Copenhagen. What was it like working with them? Any plans to work with other Game of Thrones alumni?

First off, Joe was just incredible. I watched some of his projects before he joined and we were lucky to get him. That role is a difficult one, because there’s an innocence and optimism Iver has to bring. But he absolutely nailed it. I called Charles to take on the role, because I knew he would be great. I may have oversold it a little bit—and said that it was a bigger part than it was, but he came in anyway and killed it. I’d love to work with Gwendoline Christie since we’re such good friends. Peter Dinklage as well. They’re all great people and great actors.

Did you get a chance to screen it for the Mikkelsen family?

We did do a screening for them—and I was honestly nervous about it. His family cares deeply about his legacy, with great reason. He’s their hero. So even though I wanted to be honest with the storytelling, I also hoped that I didn’t portray anything they would take offense to. I was pleasantly relieved by their reaction, which was overwhelmingly positive. His great granddaughter wrote me a long note on how she was thrilled with how it came out and that she, too, had been worried. I’m glad they believe I did his legacy justice. And I’m so proud of what my costar Joe Cole and crew accomplished.

Against the Ice is now available on Netflix. 

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