Warsaw Uprising also features specially written dialogues. Part of them are fictional, written by the film's creators, but some of them are genuine – they were recreated from the footage by lip-reading experts.
A few months after the Polish premiere, the Warsaw Uprising team began working on the English version of the film, which, they figured, needed to consist in more than just translating the script. They decided to modify the narrative by adding another character to the plot – an American pilot and journalist who is guided around the events in Warsaw by the Polish journalists.
We worked on incredible material which was silent for 70 years. Now (…) viewers can find out what the insurgents, immortalised by the authors of the footage, were talking about. We’ve worked with lip-reading experts. We sat over one shot for several hours to figure it out. Then we invited an actor to the studio. The problem was that although we knew who said what, we wouldn’t know how they said it, we could only guess. Interpreting the text is also very important, that is why recording rehearsals with the actors was strenuous.
– said Putkiewicz when work on the film was still in progress.
For the purpose of the film's sound effects, special recordings were carried out on an army training ground; recordings of the gunshots of WWII weapons, such as the Mauser rifle and VIS pistol, were made. The sound editors also had a full set of insurgent’s clothes at their disposal, including leather shoes, which enabled recordings of the sound of soldiers marching.
Sources: PAP, mpse.org, opracowanie: tk, February 2015