Revealing mistake: When the Allies are dropped from the plane into the snow and they find the dead soldier. Watch close, because the dead soldier blinks his eyes...
Continuity mistake: After Smith and Schaeffer are done rigging the trees and poles with explosives, Schaeffer gets off the motorcycle and you can see the seat of his pants is wet. As they are entering the shed, the seat of his pants is now dry.
Factual error: As the coach moves through the village near the end of the film, it drives past a tracked vehicle. The vehicle is a Hotchkiss LPz, a type of armoured personnel carrier not produced until the 1960s.
Plot hole: When Smith and Shaffer take the gondola up to the castle, they step down on the roof of the car with heavy steps. It is completely unrealistic that the Germans inside did not hear them.
Continuity mistake: When Smith and Schaffer intrude on Carnaby's interrogation, the Gestapo officer and Mary are having drinks in the café, where he makes a statement that might reveal a fault in her identity (a location in Dusseldorf). Her hand is fixed on her chin, but the next cut shows her hand fully on her cheek.
Factual error: When Lt. Schaffer is sneaking up on the German soldier, in the radio room in the castle, you see and hear the soldier changing radio station channels. Most of the music you hear playing on the radio is distinctly a 1960s style easy listening music and not 1940s music.
Factual error: Smith has the books with names in his pocket when he goes into the water, jumping from the cable car. When he shows the books to Turner, they are in perfect shape. They should have been waterlogged or at least showed some sign of water damage.
Continuity mistake: Major Smith (Richard Burton) forces one of the traitors out of the castle window on a rope. He is wearing standard battle dress. When the traitor is shot by one of the Germans, he falls wearing a camouflage smock.
Continuity mistake: In the scene where the group parachutes in, the sky is cloudy and we can see snowfall, but watch carefully, as the men make their way to the equipment containers and then to find Sgt Harod we constantly see shots switching between cloudy and snowfall, then to no snowfall and sometimes sunlight, then back to cloudy and snowfall again. This switch back and forth is even more evident on the closeups of Richard Burton.
Plot hole: In one scene, the heroes of the film (i.e. Burton, Eastwood and others) locked themselves up in the cable car control room within the castle. The pursuing Germans wasted valuable time trying to break down the heavy wooden door of the control room with axes. Why didn't the Germans use grenades or other explosives? They could have instantly blown open even the sturdiest wooden door.
Visible crew/equipment: In the scene where the Germans are pursuing Richard Burton's escaping party as they make their way towards the aircraft waiting for them, you will see the first of two pursuing German Kubelwagons being hit with machine gun fire and flipping. When this happens, you will see a cable used to flip the vehicle on the bottom left side of the screen being quickly retracted as it becomes detached from the Kubelwagon's axle.
Factual error: Schaffer and Smith are captured and the Nazis are taking them away in a car. After some fighting, the car crashes. While the Nazis fly through the vehicle's windshield, our heroes sit like they had seatbelts, which they didn't.
Continuity mistake: In the scene where they all jump from the sky tram into the water after escaping from the castle, we see the blonde woman (Mary) swim to shore. As she gets out, her hair is absolutely soaked and matted to her head. When the angle of the camera changes, we see her only this time, he hair is almost perfect and only slightly damp and is actually blowing in the soft breeze.
Continuity mistake: When Burton and the others go up the wooden staircase to approach the radio room, an upright beam is already charred by fire, but this wood only catches fire later when Eastwood throws the first grenade back at the Germans.
Continuity mistake: When Burton kicks Donald Houston off the cable car, they have been fighting on the side of the cable car. However, the next shot of Houston falling shows him falling from the front of it.
Other mistake: In the scene where Smith and Schaffer are riding with the SS in the staff car, after the car hits the snow bank, Smith picks up the SS Colonel and puts him back in the car. The Colonel is wearing a Major's collar tabs.
Continuity mistake: After looking at the Castle, Smith sends Shaffer back to the others to tell them to stay behind the tree line and he goes to the radio to contact London. When he turns to go to the radio his MP40 has the butt extended, but when he gets to the radio it's folded back again.
Other mistake: When Richard Burton is removing the light bulbs to darken the cable car as it approaches the German gunnery team, he screws them clockwise instead of counterclockwise. He is never shown actually removing the bulbs nor do they darken as he is "loosening" them.
Continuity mistake: When Schaffer climbs the rope into the castle, he reaches the top of the rope, grabs the window sill and starts to pull himself in. It then cuts to inside the room where Schaffer can be seen outside holding on to the top of the rope and then grabs the window sill to pull himself in, again.
Continuity mistake: The stub of the tree which is cut down by an explosion during the bus escape is very even and clearly cut with a saw.
Chosen answer: This is not unusual in older films. Earlier costume designers were less attentive to historical accuracy and freely incorporated current fashion trends into period movies. It was just an accepted practice and movie audiences back then were often less discerning and/or unaware of inaccuracies. Today's costumers have greater access to historical information, do more research, and strive for authenticity.
raywest ★