Just discovered your website and I love it! I've been devouring the "Name That Trauma!" entries, and of course, I have one. I remember seeing this movie as a teen in the late '70s/early '80s on a Sunday morning horror T.V. movie showcase, although the movie must have come from the '60s or late '50s.
It was an anthology movie with several segments. The one segment I remember concerned a police captain and his sergeant investigating a strange series of murders seemingly committed by a supernatural being such as a vampire or werewolf. They key in on one suspect and congratulate themselves when he is arrested or killed near the segment's end, just before it's revealed to the audience, but not the police, the supernatural being actually committing the murders is the police captain's somewhat mousy, eyeglasses-wearing female secretary.
I hope this sounds familiar to someone at your website. I've scoured books on horror film to no avail.
Thanks again for the opportunity to write in, and I'll be reading more of the website!
— Robert S.
I'm intrigued! Reminded me of Carol Kane 1997's Office Killer, which it most certainly is not.
http://www.imdb.com/title/tt0119819/combined
Sorry to say, it's not "Office Killer," but I may have to check that one out! The one I'm thinking of is definitely late '50s/early '60s because of the styles; the secretary has a bouffant hairdo, and the hair, clothes, and makeup of all the performers look to be that period of moviemaking.
It's been almost two years, so Robert may have given up by now, but I'm pretty sure that's the "King Vampire" segment from Gallery of Horror, an extremely low-budget anthology featuring John Carradine and Lon Chaney, Jr. It's on YouTube, if you want to check it out.