When Elvira Blake and Brigit Milford enter the dining room and talk to Miss Marple, Brigit is in front. When the scene cuts back to them a second later, Elvira's shoulder is in front of Brigit's. The cut is too quick for their positions to change.
When Mutti is taking photos of the other guests he takes several photos in rapid succession, without winding on the film of his box camera. This would have created a single photo with multiple exposures overlaid, but later in the movie the photos are shown as single images.
"When the inspector and the maid are on the roof, the view is of the Houses of Parliament with St Paul's Cathedral behind and to the left, St Paul's is about two miles east of the Houses of Parliament."
If the camera were looking due north, then St. Paul's should appear to the right of Big Ben but the view is to the east-northeast and all the buildings are exactly where they should be. Almost everything behind Big Ben in this view is to the east. (St. Paul's is actually 3 km northeast of Parliament.)
If the camera were looking due north, then St. Paul's should appear to the right of Big Ben but the view is to the east-northeast and all the buildings are exactly where they should be. Almost everything behind Big Ben in this view is to the east. (St. Paul's is actually 3 km northeast of Parliament.)
Unlocking a safe with a dial by just turning left and right to the right number, doesn't work. One must turn the dial every time at least 360 degrees in the same direction (clockwise & anti clockwise) to the right number to unlock it.
In the scenes on the hotel roof, a modern siren/ alarm /loudspeaker can be seen attached to the building (approx 1980s or later technology).
When Miss Marple enters the stairwell to try to get to the roof to see the first victim she somehow does not manage to see the two burly police officers until the camera has panned across to have them in frame, even though she should have seen them as soon as she opened the stairwell door..
She then meets a maid who fears her an alternate route to the scene of the crime, directly in front of the same police officers who should have had no problem hearing their plans.
She then meets a maid who fears her an alternate route to the scene of the crime, directly in front of the same police officers who should have had no problem hearing their plans.