The movie production was severely delayed and hampered by the Covid 19 epidemic. Two crew members passed away during the production of this movie. Mr. Florian Bachman, S.I.C. (analog film consultant), and Mrs. Armilde Becker both died from the effects of the Covid-19 virus. The Copenhagen sound studio facility went bankrupt in the middle of the Dolby sound mix, and international Covid-19 regulation prevented the intended release in 2020.
The Heinz cast and crew spent 16 days filming in a WW2 bunker; a claustrophobic small low-ceiling space of only 20 square meters (approx. 215 sq. feet), which was supposed to house all lighting and camera equipment, the actor, and the crew. This proved impossible. The camera equipment had to be reduced in size and volume, all lighting equipment was replaced by miniature LED armatures and the crew had to leave the room for each shot, leaving only the cameraman squeezed between the many props and a wall. Both fresh air and smoke were pumped in (and out) through various embrasures. And this was in august, with outside temperatures turning the set into a sauna. Camera and light setups were therefore mainly done during the night.
The crew was reduced to just four people during the main shooting. Directors Karel and Martin, gaffer Willem and assistant Roel were the only crew members who had to do all the jobs you normally find on a film set - the smallest crew they have ever worked with. Although cost-effective, it proved to be a real challenge.
Radios, air filter equipment, 4 bunk beds, 2 closets, weapons, water and gas cans, communications equipment, a stove, gas masks, personal belongings, suitcases, a desk, and even a canary in a cage were crammed into Heinz's living quarters of only 3 by 3 meters. Plus two cameras, a tripod, two microphones, five movie lights, lots of cables and a camera operator. The smallest camera used was the size of your hand, and the largest would only fit in the room when the cameraman left the room...
The film also portrays Heinz's lonely life in the claustrophobic little bunker of only a few square meters. From 1944, German soldiers who were unfit to be deployed on the battlefield often ended up as bunker crew for "Atlantik Wall" bunkers across Europe.
They lived in cramped spaces devoid of light and fresh air.
A minority managed to survive on contaminated water, crackers, and Crystal Meth (Pervitin) tablets. Over 200 million Crystal Meth tablets were delivered to the German forces over the course of the war; driving many of them mad...
From the end of 1944, German soldiers like Heinz survived on soiled water, potato soup, crackers, and Crystal Meth (Pervitin) tablets. Over 200 million Crystal Meth tablets were supplied to the German troops during the course of the war. This explains the nightmares and irrational behavior of Heinz in the movie.
All the props used in the film, from furniture to Heinz's underwear, are 100% authentic and date from the Second World War period and were provided by several war museums and private collectors. The authentic German "mother cross" was supplied by a 94-year-old German mother, and a fully restored early model of the Arriflex 35mm. camera from that period was used for selected shots. Even the gun turret and viewing platform with periscope were completely authentic and fully functional, as well as all weapons used in the movie, although no weapon was actually fired in this movie,
The makers omitted most swastikas and other Nazi emblems and insignia, except those essential to the story or historical accuracy.