The film is based on series of books by Rezun Vladimirh Boghdanovich aka "Victor Suvorov", which described true story and events. I recommend it to watch as a counterweight to action-drama entertainment movies in "James Bond' style -- not to diminish quality of the latter, but to just realize, the actual inventions in real-world spying were even more weird, than the ones of ol' good Flemming. It may be significant, that the materials for the standalone version were also remixed as six episode TV series (atleast in Poland, but I think, this was shown in Germany, Austria and Ukraine broadcasting too). Somebody commented it as "Thriller" -- the most scaring thing is, it is all true...