The castle has had a history of ghostly sightings and a spirit cleansing was performed there a couple of months prior to shooting after one of the owners had died. No strange activity was reported by the cast or crew during filming.
The film was shot entirely in Switzerland, in an actual classified castle. The crew and cast lived in it for six weeks together during principal photography.
Christopher Jacobs, for his role as Virgil, wore a pair of shoes two size smaller than his actual size during the whole shoot as they were the only ones available at the time that fit the look of the character.