Revealing mistake: When the two gangsters open the car trunk to move the bagged dead body, it moves during the duration of the scene. (00:28:40)
Continuity mistake: When Mr Stringer picks up Miss Marple from Akinthorpe Hall in his car, Alexander, as a harmless joke, has tied a string of old shoes and empty cans to the car and put a sign 'Just Married' on the back of the car. As the car first drives off, the sign is seen falling away, but when we get a different shot, the sign is well secured.
Continuity mistake: Chet visits his friends that are playing poker. He falls asleep and wakes when he hears the news on the radio. The band aids on his wound change abruptly position in close-up. (00:12:10)
Continuity mistake: Doris picks up the phone and there's a cutaway shot on Johnny playing his guitar as he listens. The stockings Doris tossed at him are gone from the guitar head, but they are back when the phone call is over. (00:05:10)