Father Verecker says he's figured out Steiner's plan to "assassinate" Churchill. Pamela overhears and flees, first to Joanna and then to the Americans. She tells Joanna that the Germans mean to "kidnap" Churchill, but tells the Americans that the plan is to kill him.
The windshield of the Jeep that crashes into the river is shot out as it is driving past the windmill, but is intact in the next shot as it leaves the road.
When Steiner and Devlin find Arthur's body in the cottage, the blood stain on the door from when Molly shot him has mysteriously disappeared.
When Sgt. Brandt carries one of his dead comrades off the boat in the harbour on Alderney, he gets blood on the right shoulder of his jacket. When he walks up the stairs, where Colonel Radl is standing, the jacket is clean. Later, when Devlin is in the pub, the jacket is bloody again.
When Oberst Radl (Robert Duvall) visits Himmler (Donald Pleasence) for the first time, his service dress cap correctly carries a miniature Edelweiss symbol between the eagle and the cockade as he is a member of the Gebirgsjaeger (Mountain Troops). When he meets Steiner (Michael Caine) for the first time on Alderney, later in the film, this device is absent.
The Germans repeatedly refer to traveling by "E-boat" throughout the film. This was the Allied designation for the type. Germans would have called them "S-boots," short for Schnellboot, or "fast boat."
The ancient parish church of an English village in 1943 would not be Roman Catholic. Such churches have been Anglican since 1559. Since 1810, the Roman Catholic Church has re-acquired several "ancient parish churches" from the Anglican Church. Some small villages in the United Kingdom have predominantly RC residents, albeit not very many; however, the religious preference would have been influenced by the local nobility. Some of the nobility, such as the Duke and Duchess of Kent, are Roman Catholic.
Colonel Radl's aide, a senior sergeant, wears a beard at the beginning of the film. German regulations prohibited the wearing of beards, except in the front lines and in other circumstances where shaving was not possible.
There is a signpost in the Norfolk village clearly showing directions to nearby towns, including King's Lynn. It is common knowledge that all such signposts were removed for the duration of the war in order to disorientate and confuse invading German troops.
Some of the carbines carried by the Rangers have perforated metal handguards, which were never used on U.S. military carbines.
When Devlin has climbed into the cockpit of the plane, Col. Steiner is still speaking to him - they would not be able to hear each other with the engine running.
During the scene at the port on Alderney, we see an army truck that has a Wehrmacht number plate (beginning WH), but which carries the 'wolf hook' insignia of Das Reich, an SS division.
When the American Rangers are travelling towards the church where the villagers are being held, there is a Reliant Regal in a farm yard on the right hand side of the image - this model was only introduced in 1953.
In the culmination, many scenes are supposed to be late at night. But despite it being night, these scenes take place under a bright blue NIGHT time sky. Obviously, this scene was filmed during the day, using a filter to darken the images, which was not anywhere close enough to being dark enough to mask the blue of the daytime sky.
When the Colonel (Hagman) goes to Gray's house, just before he kicks the door open, the latch lifts up (presumably by someone inside), to make it easier to kick open.
On the beach when Molly asks Devlin how he knows her name, he says "George Wilde told me, in the pub".. Devlin did learn her name in the pub, but it was when Arthur Seymour warned him to "stay away from Molly Prior". So George Wilde didn't tell him, Arthur Seymore did.
When Col. Steiner knocks one of the guards unconscious towards the end of the film, he impersonates the call-sign "Delta 2". The NATO alphabet which used that term for D ("Delta") was not adopted until 1956. The WW2 call-sign would have been "Dog 2".
When Capt. Clark - after having stormed the church - reports back to his commander, there is a fifty-star (instead of a 48-star) USA-flag standing behind his superior.
The carbines carried by the American Rangers are selective fire M2 models. These did not enter service until early in 1945.
The bazookas are the post-war (Korean War era) M20 3.5" model, not the smaller and less effective WWII 2.36" M1 or M9 model.
Just about all the men's hairstyles are reflect the longer look of the mid-1970s, not the shorter military look of 1943; likewise the sergeant's beard would not have been tolerated by wartime military regulations (although not mentioned in the film, the book makes it clear that Steiner gave the man special dispensation to grow a beard, to cover a shrapnel wound to the chin).
There is a scene when one of the invading soldiers sits down to play a church's pipe organ. His hands are shown on the keys and it is blatantly obvious that he is not playing the technically challenging music that we hear.
When Radl is climbing the stairs to his office he can be seen to be speaking, and his assistant Karl is also seen to reply. However, there is no sound of either man speaking, and the only sounds heard are Radl's footsteps on the stairs.
The story is set on the North Norfolk coast, which is flat and marshy (and the Donald Sutherland character takes the job of Marsh Warden). Unfortunately many of the coastal shots show cliffs, bays, creeks and sand dunes which just aren't there. For example, the wooded creek where the converted MTB picks up Hans, could not be in North Norfolk.
The shadow of the boom mic is visible in the top-right-hand corner of the screen whilst Devlin directs Steiner to the back of the church to show him the escape route he has found.
One of the Polish Jews curses in Finnish.
The character of Liam Devlin is supposed to be from Belfast in Northern Ireland, but his accent is from somewhere in the Republic of Ireland, not the north and certainly not Belfast.
When Kurt Steiner and his men confront the SS detachment, he addresses their leader as "Herr Gruppenfuhrer". However, he has three oak leaves and two stars, which makes him an Obergruppenfuhrer, which is one rank higher. Unless Steiner was trying to be disrespectful, he should have known better (or perhaps Michael Caine flubbed the line). The actor is properly listed in the credits as an SS-Obergruppenfuhrer.