Invisible Monster Week! We’ve already had this beastie as a visible monster, but really, you can’t go Invisible Week and leave him off. Kudos to the filmmakers, who managed to make the invisible monster nearly as scary as the really, really neat visible ones later. By counter-intuitively using stop-animation for the ‘invisible’ part, along with some really gruesome sound effects, they made this part of the film nearly as good as the climax. Of course, it helps when you have one of the greatest monsters of the era after you do your reveal.
(Having Kim Parker in a towel didn’t hurt things, either.)