Tronstad establishes contact with the War Ministry and a plan to destroy the Hydro facilities is drawn up. In Rjukan, new managing director Erik Henriksen is confronted with sabotage of the heavy water facility.

The Americans insist on bombing the heavy water factory, but Tronstad persuades the Allies to send in a team of Norwegians instead. In Germany, Nobel Prize winner Werner Heisenberg promises a breakthrough in the development of a Nazi atomic bomb.

April, 1940. Germany invades Norway and orders a doubling of production at the heavy water plant in Rjukan. Norwegian professor and reserve officer Leif Tronstad escapes to England to warn the Allies about what he believes is an effort to build a German atomic bomb.