The swastika that Kindler is drawing on the notepad is running in the wrong direction.
Two palm trees are visible in the first scene depicting the fictional Connecticut town.
Near the start of the movie when Meinike gets off the ship and is going through passport control, we hear him say to the officer 'I am traveling for my health', but his lips don't move because as he's approaching the checkpoint, the audience hears his thoughts as to why he's traveling.
Right before they open Meinike's suitcase, both Mr. Wilson & Mr. Potter are shown moving the same checker piece. This may, indeed, be a simple continuity gaff. However, it may also mean to indicate that neither man's mind is focused on the game at hand.
In the beginning of the film, Mr Wilson breaks his pipe near the base. When we next see the pipe it is taped near the mouthpiece.
When Wilson runs the Concentration Camp footage for Mary Longstreet, we see several shots of her face with the flickering light from the screen reflected onto her face. When the film runs out of the projector, the light on her face continues to flicker as if film is still being projected instead of being a bright white light.
The sign in Haroer School reads "Anyone using apparatus in this room does so at their own risk." Grammatically incorrect mix of singular and plural. - it should read : People using apparatus in this room do so at their own risk. or: Anyone using apparatus in this room does so at his own risk.
Judge calls Mary his daughter sister twice, after seeing her reaction to the film shown by Edward g Robinson.
In the final checkers game between 'Professor Charles Rankin' and 'Mr Potter', parts of a crew member's back and head can be seen reflected in the mirror behind Potter. Potter stands up, Rankin says "You know, uh, Mr. Potter, you're a bad influence", and as the camera pans to follow Potter, the crew member (probably the focus puller) can be partially seen in the mirror. He leans out of view momentarily, but then leans into view again as the camera pans back with Potter.
When Konrad Meinike visits a photographer 5&1/4 minutes into the film, the shadow of a boom mic can be seen moving in the upper left corner of the screen.
Mr. Wilson is in the café and the owner tells the soda is a nickel. Wilson gives him a large coin (possibly a half-dollar), but does not get any change.
As Mr. Potter is pulling out Konrad Meinike's possessions from the suitcase, Mr. Wilson calls out the items in order without ever actually looking at the suitcase itself.
Mr.Wilson is hit on the back of the head and knocked out in the gym. The next time we see him he has a medical patch on his forehead.