Mario Adorf wanted to play in this movie, preferably the role of Hermann Willié, which went to Götz George, or the role of Fritz Knobel, which went to Uwe Ochsenknecht. Adorf later admitted that he had been offended for a few years, that Helmut Dietl didn't cast him in any role.
"Stern" magazine, which was releasing the fake Hitler diaries in real life, released a podcast in 2019, in which they were also discussing the movie. There they mentioned that the story is very close to the real events and very little was invented, with the exception for the character's names. Former editor in chief Michael Seufert told then that director Helmut Dietl was asked, why various absurdities from the real story were not included in the movie. He said that some of the real events were so absurd that the viewers would take it as too crazy and would be angry about Dietl.
Based upon a true story.
The character Freya von Hepp, who is portrayed as the niece of Hermann Göring in the movie, is based on Edda Göring, who was in real life the daughter of Hermann Göring. For 5 years she was also friends with the journalist Gerd Heidemann, on whom the character Hermann Willié is based on.