Heisenberg is named director of the Kaiser Wilhelm Institute; and the Gunnerside team succeeds in blowing up the factory, but the Nazis mount a major search for the saboteurs and order the rebuilding of the heavy water facilities.
The Americans want to bomb the heavy water factory, but Tronstad convinces the Allies to instead send a team of Norwegians; and, in Germany, Werner Heisenberg promises a breakthrough in the development of a Nazi atomic bomb.
Tronstad makes contact with the War Ministry and a plan to destroy the water facility is developed; in Rjukan, new managing director Erik Henriksen faces sabotage of the facility; and an operation with 34 British commandos is hit by a severe storm.
The series about the Nazi atomic program begins in April 1940 with Germany's invasion of Norway and the order to double production at the heavy water plant in Rjukan. Norwegian professor and reserve officer Leif Tronstad, meanwhile, escapes to England and warns the Allies about Germany's plan to build an atomic bomb.