Original release prints included a "Whodunit Break", a 60-second recap of previous events, after the last two characters discover the body of Mr. Owen's eighth victim. The Whodunit Break is missing from most subsequent prints.
When Mike Raven (Fabian) is playing the piano, his bow-tie is untied. However, when the others are examining the record player, he is shown pacing in the background with his bow-tie tied. In the next shot, it is untied again.