This movie has been made during communist regime in Poland and therefore showed Poles as allies of Stalinist Russia. It was not true. The independent Poland performed its own secret secret operations against 3rd Reich and the Stalinist Russia did the same but not in alliance. Many best Polish stars have played, shootings were very realistic. The film was very popular in Poland, in the USSR and in... Denmark. In some cases Germans have been shown as stupid slaughters. For example, second lieutenant (Oberleutnant) Kloss has been awarded by Iron Cross by Hitler (shown from the back, however) for discovering a plot against main Nazi leaders. Wilhelm Canaris is also shown (a part of face only). The role of a SS officer Brunner (Emil Karewicz) is a masterwork.