William Castle: [gimmick] Used a gimmick called "Emergo" in theaters. When the skeleton rises from the acid vat in the film, a lighted plastic skeleton on a wire appeared from a black box next to the screen to swoop over the heads of the audience. The skeleton would then be pulled back into the box as the skeleton in the film is "reeled in". Many theaters soon stopped using this "effect" because when the local boys heard about it, they would bring slingshots to the theater; when the skeleton started its journey, they would pull out their slingshots and fire at it with stones, BBs, ball bearings and whatever else they could find.
The films opening was something of a jump scare gimmick, the total darkness accompanied by horrible noises echoing in a large movie theater would have been very terrifying, the effect is somewhat lost on a modern viewer watching the film on a television screen without the volume and scale to provide shock of theatrical sound and darkness.
The Ennis Brown House in Los Angeles, designed by Frank Lloyd Wright and built in 1924, and now listed on the National Register of Historic Places, was used for the exterior shots of the haunted house during the film's opening sequence.
William Castle had related the story of meeting Vincent Price on a day when Price had learned that he had been passed over for a part. Over coffee, Castle described the premise of this picture. Price liked the idea and it led to a two-picture collaboration, this and The Tingler (1959).
The failure of the original copyright holder to renew the film's copyright resulted in it falling into public domain, meaning that virtually anyone could duplicate and sell a VHS/DVD copy of the film. Therefore, many of the versions of this film available on the market are either severely (and usually badly) edited and/or of extremely poor quality, having been duped from second- or third-generation (or more) copies of the film.
The popular theme music originally had haunting lyrics by Richard Kayne, but only the orchestral version was used in the final film. For the record, the lyrics went as follows: There's a house on Haunted Hill / Where ev'rything's lonely and still / Lonely and still / And the ghost of a sigh / When we whispered good-bye / Lingers on / And each night gives a heart broken cry / There's a house on Haunted Hill / Where love walked there's a strange silent chill / Strange silent chill / There are mem'ries that yearn / For our hearts to return / And a promise we failed to fulfill / But we'll never go back / No, we'll never go back / To the house on Haunted Hill!
Julie Mitchum Sader (sister of Robert Mitchum) was wearing a large Bahá'i ring on the set. The director noticed this and thought it would add a slight bit of mystery to her character so he arranged one shot with an extreme close-up of the ring. The inscription on the stone is Arabic calligraphy that translates as, "God is most glorious."