The end of 1944 is approaching and Nazi Germany is pinning all its hopes on the development of new, devastating weapons. These include the terrifying V2 rockets. At a remote base in the woods out of reach of Allied bombing, young engineer Rudi Graf supervises the final modifications under the strict control of SS troops. Meanwhile, a young Englishwoman, Kay Caton-Walsh, joins a special unit of British intelligence. Their must can change the course of the war, even if it does not happen on the battlefield...