It will be no spoiler to reveal that there’s nothing truly supernatural going on—House on Haunted Hill follows the venerable formula of “old dark house” mystery stories in which spooky goings-on are inevitably revealed to be costumed criminal conspiracies. But the reveal here asks you to ignore a number of elephant-sized issues. To produce all the effects we have seen, this hundred-year-old house would have needed an infrastructure and behind-the-scenes personnel on the scale of a major theme park.
The gimmick in House on Haunted Hill was a new film process called Emergo, in which, the trailers and ads breathlessly promised, a ghost would actually emerge from the screen and soar over the audience. It all transpires in the final reel, for less than a half minute. After Price appears with the puppeteer controls by which he has just manipulated a weaponized skeleton, a life-sized duplicate of the same would suddenly drop from the side of the screen and jiggle its way over the audience. Later that year, for The Tingler, Price and Castle teamed up with an even more ambitious gimmick, Percepto, which involved individual theater seats being equipped with electrical buzzers meant to be the noise of a centipede-like creature that feeds on fear, set loose in the darkened theater and very, very hungry.
UNIVERSAL PICTURES, 1932