the murder of a prostitute in german-occupied warsaw in 1942 causes major grau of the abwehr to start an investigation, as she was also a german agent. his evidence soon points to the killer being one of three german generals: general von seidlitz-gabler; general kahlenberge, his chief of staff; or general tanz. grau's investigation is cut short by his summary transfer to paris at the instigation of these officers.