Based on true events of World War II, this five-part miniseries follows Leif Tronstad, a Norwegian scientist taking refuge in England. When the Nazis commandeer the Norwegian factory where he oversaw experiments, and repurpose his innovations to produce an atomic weapon, he must carry his guilt while simultaneously advising the British to stop them. When it becomes clear that the factory must be destroyed, Tronstad must convince Allied command to let him plan a mission carried out by commandos rather than firebombs, as any attempt to bomb the facility will put three thousand civilian lives in danger. Ten Norwegian refugees are assembled, all expert skiers, to drop into occupied Norway and carry out the mission on foot—or rather—on ski. Led by young resistance fighter Joachim Rønneberg, each man faces his own difficulties as the commandos shoulder the weight of those three thousand Norwegian lives.