After Shayne demonstrates the magic wand trick, the stage hands run from the table. One of them runs right through the thread attached to the wand but doesn't snag it.
When Mike enters the dining room to look for clues, the dead woman blinks. Her eye can just be seen through the candle holder when she blinks.
In Davis apartment Mike hits the inspector over the head with a vase knocking him unconscious, but when he meets him again later he has a black eye like he was punched in the face.
For scenes in Inspector Pierson's office there is a lot of reverberation, particularly when William Demarest shouts his lines. This lack of sound dampening reveals that the scene was shot on a large sound stage.
The theatre displays outdoors a life-size cardboard cutout of Mary Beth Hughes in harem costume. However, the harem costume in the show is worn by the chorus girls. Mary Beth Hughes is a featured performer.
When they show the cast credits at the end of the movie they show Ben Carter as Rusty and Mantan Moreland as Sam. In fact Ben Carter played Sam and Mantan Moreland played Rusty.