Very little of the filming took place in the actual mansion. The mansion's design in reality is extremely cramped, making filming very difficult. As such, most of the mansion's interior needed to be re-created on soundstages.

Goofs

When the mansion's exterior is first shown in daylight, the sun is depicted as coming from the right side of the frame when the camera is facing the mansion's front facade. This is impossible, as the mansion's front facade faces due east, and the right side of the frame would be north. In San Jose, California, which is in the temperate zone of the Northern Hemisphere, the sun cannot shine on the north side of the mansion.

