"It was a fever dream": Lucas Tønnesen on how Netflix mystery thriller 1899 took him to Dark places

With Netflix's new, multilingual thriller-drama series 1899, 22-year-old Danish actor Lucas Tønnesen took on the most challenging project of his career so far. "It was really a fever dream," Tønnesen recalls of the experience. "When I look back, I can get so emotional because it's been such a journey and everyone's been giving their absolute max."

Created by Jantje Friese and Baran bo Odar, the masterminds behind Netflix's hit supernatural thriller show Dark, 1899 offers its viewers a mind-bending mystery topped off with an unnerving, eerie atmosphere. As a migrant steamship heads to New York with passengers from all over Europe, everyone on board seems to have a painful secret from their past that they're hoping to sail away from while looking forward to starting fresh in the new century. However, upon discovering another migrant ship adrift on the open sea, the passengers' hopes and dreams quickly turn into a chilling nightmare…

Taking on the role of Krester, an enigmatic young Dane travelling to New York along with his family, Tønnesen was tasked with the most demanding part he has portrayed so far. "It was very different from what I've done before. Getting into Krester’s mindset was really hard on me because I'm a really positive guy," Tønnesen explains. "So going the other way and just being absolutely miserable for months and months takes a toll on you, but I was very lucky to have the best cast mates around me."

Krester, an emotional character so gloomy and complex that you'll spend the whole first season trying to figure him out (amongst other baffling events), is, according to Tønnesen, "The furthest way [from myself] that I've ever portrayed anyone, which is also really interesting because you then discover something about yourself that you didn't think was in there."

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Tønnesen's love for Dark helped the actor to tap into Krester's despair, aiding him in finding the right tone for his character. "In my first-ever interview in 2018, I said that I really wanted to work with the Dark creators," the actor says. "Now, I had the chance to show what I'm made of and here was an opportunity to do it in a cool show."

Providing an extra challenge to Tønnesen whilst filming 1899 was that he was simultaneously filming another Netflix production: the fourth season of the ultra-popular Danish political drama Borgen. Hopping between sets and countries (1899 was filmed in Germany, Borgen in Denmark) and sometimes spending the night in a car while travelling, Tønnesen says the draining double-filming situation, perhaps surprisingly, gave him a push to really excel in his performance as Krester.

"When you don't have much energy, you can go two ways," he says. "You can go dead and there's nothing inside of you that can come out - no emotion. Or, you can be so tired that one push and you start sobbing - everything comes out. I was in that state and I could let everything go." Filming Borgen at the same time as 1899 also gave Tønnesen a breather from the heavy character of Krester; his role as the happy and positive Magnus Nyborg Christensen, the son of Denmark's prime minister, proved to be the perfect antidote.

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Although he'd previously been involved in other Netflix productions such as The Rain, in which he played lead character Rasmus Andersen, Tønnesen found being on set for 1899 was like nothing he'd experienced before. Besides being the biggest production the actor had been a part of, the show's cutting-edge, virtual set design raised it to another level. "First of all, you get to hear that 95 per cent of the show is going to be shot on set and you're going to be like 'we're on a ship, how does that make sense?' But very early on, the volume got introduced," Tønnesen says, referring to an enormous LED wall.

1899 was the first Netflix production to use this kind of set design, and the volume provided the cast and crew with an entirely new filming experience. "Having this technology, it was everything for the show," Tønnesen says. "Seeing the Atlantic Ocean in front of you, and they could just turn it into a sunset if they wanted to, or turn it into stormy rain if they wanted to… And for us, having the feeling we're there. It's so much better than looking into a green screen."

After nine months of hard work, in November 2021, the filming for the first season of 1899 wrapped. Tønnesen admits it was intense, but is quick to say he would "do it all over again."

To balance out his hectic set life, Tønnesen unplugs in wholesome activities, including playing chess, hiking in nature and spending time with his loved ones. So does he also hang out with other next-gen rising Scandinavian actors, like the cast of Young Royals? "I actually met Omar [Rudberg] at Copenhagen Fashion Week, we were sitting next to each other at a fashion show and then we started talking, he was super sweet," Tønnesen says. "The thing is, we don't all live in the same country. But when we go to different countries, we of course hit each other up. Everyone is super cool and sweet, it's such a talented generation of actors and we are all rooting for each other."

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Post-1899, Tønnesen has hardly rested on his laurels. "I'm coming out in two feature films next year. One Swedish and the other one German," he says, though won't be drawn on further details. Apparently, in addition to being fluent in Danish and English, Tønnesen has also mastered German and Swedish. "Besides that, hopefully, we will go into production on season two of 1899," he adds. "This is meant to be a three-season show, so creating enough mystery for later seasons to unfold was a really big thing that I wanted to do. After the first season, fans are going to be left with 'what the f**k?', 'I want to watch one more' and 'when will season two come out?'”