Winter has fallen on the South Pole. The sun will soon disappear for the next six months. A small team of scientists, known as the Winterers, will remain at the Polaris VI Antarctic Research Station to continue their innovative research. Their work is crucial in the fight against climate change and they are under the command of renowned biologist Arthur Wilde. But when spring comes, summer commander Johan Berg returns to the station only to find most of the team dead or missing. A killer is on the loose and Annika, Johan's wife, is missing too. If he wants to find her alive, he will have to trust Maggie, the young doctor who is profoundly shaken and apparently the sole survivor from the group... or, is there someone else who survived?