At the end of 1943, Einar sent a secret report saying that the Weimock chemical plant resumed the production of heavy water after one year of repair. Almost immediately after receiving the telegram, London sent the Royal Air Force to carry out air strikes. The plane of the eighth aviation division of the United States immediately took off and bombed the power station of this factory. Everyone wants to blow it up. However, repeated and violent air strikes did not produce much effect, but the price paid was very high, and many bomber pilots and Norwegian civilians were sacrificed. After that, the Germans decided to move all the equipment for refining and storing heavy water in Weimock Chemical Plant to an underground base in Germany.

Obviously, Germany's plan to transfer heavy water should not be allowed to succeed. In this case, Churchill put the weight of trust on the "Swallow", because their outstanding performance is enough to undertake this important task, and no one can replace them. The special operations command once again undertakes the mission of destroying and cutting off the heavy water supply in Germany.