When Gen. Schottland is in the forest trying to radio the allies, he is confronted by a soldier carrying a British Sten sub-machine gun. In the next scene it is revealed to be a German soldier and now he is carrying a German MP-40 sub-machine gun. In the next scene it switches back to a Sten.
When General Schottland is driving back to Berlin from the front on the autobahn, his car passes a truck on the side of the road. When he is fleeing Berlin and going in the opposite direction his car passes the same truck, although it should now be on the other side of the autobahn. It looks like the same clip was used twice, once for coming and then again for going.
Muller orders Reinisch to stop the tape in the middle of playback. However, it can bee seen that the tape has already finished and the take-up reel is turning rapidly, having taken up all the tape, and the feed reel is virtually stationary.
Use of reel to reel tape recorder. Whilst Americans may believe tape recording was a post-war development, it is a fact that Germany had built and developed practical tape recorders in the 1940's. They were used in both military and broadcasting situations. After the war, the Ampex corporation was given the German technology as a reward for their war work and they began to manufacture tape recorders in the US. The Ampex model 300 was a very close copy of the German production unit. Some industry journals even suggested that Ampex sold existing units seized from German warehouses before they began manufacture. However, the unit shown in the film is not an Ampex 300 and it is unlikely that German tape would be mounted on plastic reels as shown.
The information would have been unnecessary as the Allies had ULTRA. But in 1958 the general public were completely unaware of ULTRA, and that Bletchley Park (following on from Polish efforts) had broken the Nazis' codes. So it is not surprising for a movie to be made that attributed the Allies' intelligence successes to a story such as this one.
Several transitional scenes (staff car traveling on the autobahn, refugees streaming through Berlin) are used more than once.
After Gen. Alex Schottland shoots the soldier and is having trouble getting his vehicle going; the supposedly dead soldier can be seen moving his right leg. He was in a coma and Gestapo Chief Muller uses him to identify the general who shot him after his partial recovery (he is shown in a wheelchair in Muller's office). While lying next to the car, the soldier also raised his head twice.
In the final shots, a large British flag attached to a mews gate is in fact the Flag of Great Britain, not the Union Flag. The former lacks the diagonal red cross of Ireland, the St. Patrick's Saltire. It's more likely that the location dressers unknowingly picked the pre-1801 flag from the movie studio prop store than that people in 1945 found such a flag when correct Union flags would have been far more available to celebrate the end of the War with.
When Schottland opens his newspaper to find his connection, the ads for Nuremberg Eggs are in English whilst the rest of the paper is in German.
Alexander Knox keeps mispronouncing Kaltenbrunner's name as though it were a 'u' with an Umlaut, which is not the case.
Although the story is taking place in the years from 1939-1945, Gia Scala's clothes and hairstyles are strictly 1958, the year the film was made.
Both Jack Hawkins' and Gia Scala's apartments are very mid-century modern, despite the story taking place a couple of decades earlier; no hint of wartime damage or shortages is seen or even hinted at.
Although exterior scenes in the 1944 sequences show the ravages of war, both Jack Hawkins and Gia Scala's apartments are clean and in perfect condition.