Continuity mistake: During the middle of the film, a butler comes in and out of the Dictator's office several times repeatedly. The door is open and shows the corridor outside the office, casting the shadow of a window off-screen. The shadow changes from small to big bewteen shots.
Continuity mistake: There is a scene when they are all in the press room when he's inside the desk. As Hildy goes to get water you can see she's wearing the black heels she's been wearing throughout the movie. In the next shot as she walks behind the table, if you look through the table legs you can see she's wearing a pair of flat white slippers/loafers.
Continuity mistake: Near the beginning Harriet Vane produces tokens for herself & Lord Peter Wimsey of miniature handcuffs with one cuff "open to symbolise we're giving up on crime". She puts hers on as a bracelet. Immediately after & several times throughout the film it's clear hers is a set of closed handcuffs.
Continuity mistake: As he is talking, Jimmy Stewart is writing on small boxes and placing them in a pile. He sets one down, and when the camera changes, he's suddenly got one in his hand again. (00:27:35)
Continuity mistake: Near the beginning of the film, in the foyer of the hotel, Joan Fontaine is seen drinking coffee but in the next shot she's reading the newspaper.
Continuity mistake: The car the deputy and contractor drove up in disappears. That road was one lane which would have been a hell of a back up job. Then almost instantly the 2nd car full of deputies flies up like a bat out of hell "hey what's going on" indicating they didn't speak to the contractor because they had no idea what occurred. The next sequence Casey points in direction from where the deputies just flew up. The complete opposite of where the woman was actually lying. The poor woman would have been ran over. (01:11:53)