In 1909, Danish explorer and Captain Ejnar Mikkelsen sets out to lead an expedition in Shannon Island, situated in East Greenland. His mission is to uncover the missing records of the unfortunate Denmark expedition. After a failed initial attempt, where his team found themselves stranded on their ship amidst the frozen Arctic landscape, Ejnar perseveres. During that first try, he and his crew member Jörgensen attempted to locate the missing expedition, but after Jörgensen suffered frostbite, emergency amputation was required to save his leg.
Undeterred, Ejnar manages to find an ally for his second journey in the form of engineer Iver Iversen, while the rest of the crew remain behind. Armed with a diary from a crew member of the Denmark expedition, which holds a crucial map detailing their intended Arctic journey and the location of a claiming stack of stones, Ejnar feels confident. If they fail to locate this stone pile, the Americans would lay their claim to the Arctic territory.
Unfortunately, the mood among the remaining crew is one of demoralization, as they are reluctant to risk their lives for an uncertain adventure. Iver, being the ship's motor engineer, finds himself with nothing to do while they remain stranded. Although not skilled with sled dogs, he reluctantly agrees to join Ejnar, defying the warnings of the crew about the -40 degree temperature and polar bear threats.
On March 1, 1910, they embark on their journey. Ejnar instructs Jörgensen to await their return until August, at which point the crew should leave if they are not back. As they progress, they face numerous challenges, including hauling their supplies over treacherous frozen cliffs, as Ejnar remains emotionally distant from Iver.
On Day 26, Ejnar recounts the harrowing discovery of the frozen remains of the Danish expedition, where he found the diary that leads them to the next stack of stones. As days go by, they agonizingly lose two sled dogs early on; Iver’s lead dog, Bjoern, tragically falls into a ravine during a supply run. This incident costs them valuable dog food and other supplies, plunging them into dire straits.
By Day 48, they manage to escape the ice cap, but not before learning of the American claims on Greenland, which further complicates their mission. The unrelenting cold forces them into desperate situations, leading to the heartbreaking decision to sacrifice their remaining dogs for sustenance. By Day 84, they finally find the long-sought stack of stones, alongside a historical letter from the explorers dated 1907. This correspondence paves the way for proving that the Peary channel never existed, ensuring the northern grounds of Greenland remain under their claim.
As the days drag on, culminating in Day 132, Ejnar and Iver are still battling the elements, losing more dogs to the relentless cold. Eventually, they encounter a polar bear. While hunting for seals, Iver rushes back to defend Ejnar, but the bear has already attacked and killed two of their dogs.
Ejnar manages to recover but decides to dispose of the remaining sled and dogs to travel lighter as they approach the final stretch back to their ship, the Alabama. In fear of losing his journals and crucial evidence, Ejnar builds a protective stone pile during a treacherous crossing.
Months later, the duo returns to Shannon Island and are devastated to discover the rest of their crew has abandoned them, leaving them stranded. They take refuge in a cottage constructed from ship remnants, where they endure two harsh winters, thanks to leftover food supplies. Back home, the remaining crew members plead with Minister Neergaard for a rescue mission, but their appeal is met with refusal as he reprimands them for allowing Iver to accompany Ejnar, citing he was inexperienced.
Unable to wait for help any longer, Ejnar makes a fateful decision to return for his journals after a nightmare about the bear destroying their claims. On Day 439, they find their records barely intact. However, by Day 471, they return to discover a note indicating a rescuer had been there, prompting a fierce argument between Ejnar and Iver over the absence of communication.
As the days stretch to Day 793, summer finally graces them with hope. Ejnar, now lost in hallucination, imagines Naja rescuing him in a hot air balloon, his mind playing tricks. A comical yet tense exchange leads to an attempted shooting of Iver, but soon they are finally rescued in 1912 by Jörgensen, bringing an end to their harrowing ordeal.
In a poignant conclusion, an epilogue reveals that Ejnar married Naja a year later, while Iver never again set foot in the harsh Arctic terrain.
