This episode uncovers the development of Adolf Hitler's vengeance weapons, how British authorities became aware of the menace and what actions were taken to prevent and to delay their use. It features rare footage of the V-1 flying bomb, the V-2 missile and Operation Hydra, the bombing of Peenemünde and details of Operation Most III, along with interviews featuring Jones, Duncan Sandys, Albert Speer, Constance Babington Smith, Roland Beamont, Janusz Groszkowski and Raymond Baxter.