The photo of Vanessa's (Reese Witherspoon's) father that she shows to Bob (Kiefer Sutherland) is of mass murderer Richard Speck.
Reese Witherspoon used an exaggerated version of her natural Tennessee accent for the role of Vanessa Lutz.
Originally rated NC-17, reduced to R after the removal of some explicit dialogue and toning down some of the violence.
Two-shots including Dan Hedaya and Brooke Shields make it appear as if they are close to the same height, but in fact, Shields (at six feet) is a full three inches taller than Hedaya (five feet nine inches), and wearing the two-inch white pumps shown in the film, she would have towered over him.
Kiefer Sutherland's make-up in some parts of Vanessa's nightmare is from his early make-up tests. The more extreme make-up was scratched because it took six hours to apply, and the shooting schedule wouldn't allow the time for it.