Trivia: At the beginning of the film Lucy and Ray watch a videotape called 'Murders, Madmen and Psychopaths', with the news report of Johnny Charles Bartlett. The reporter is a genuine TV reporter in NZ (where the film was shot), cast presumably due to her real American accent. (00:11:10)
Trivia: R.Lee Ermey gives a great performance as "Sgt Hiles" in this film. He has played similar "over the top military characters", such as, in the TV series "Space, Above & Beyond" and other movies and TV shows. One reason he is so effective in these roles is his personal history as a real Staff Sergeant, and later a Gunnery Sergeant in the Marine Corps.
Trivia: During production, Peter Jackson personally purchased over 30 new computers for WETA in order to help get the special effects done on time. After the film was complete, he tried to think of another project that he could work on in order to utilize all of the computers he purchased for the film, not wanting them to go to waste. He thus decided to work on a fantasy film next - and this project would later end up becoming his famed "Lord of the Rings" film trilogy.
Trivia: To date, this is the last major live-action film Michael J. Fox has starred in. Due to his struggles with Parkinson's disease and his desire to spend more time with his family, he decided to dramatically cut down on the jobs he took after completing "The Frighteners." Since its release, Fox has mainly focused on voice-over work and supporting roles in film and television projects, as they require less of a time commitment.
Trivia: Early on in production, "The Frighteners" was in consideration to be the second "Tales from the Crypt" movie, after "Demon Night," and before "Bordello of Blood." Producer Robert Zemeckis liked the story so much, however, that he decided to produce it as a stand-alone work.
Chosen answer: For the most part, the actors playing the ghosts were shot separately on blue-screens, and then comped into the scenes. (By removing the blue background through a process called "color keying", and placing them over the scenes) They were simply given a blueish glow and made semi-translucent to complete the effect. It was pretty cutting edge back in the 90's, but nowadays, it'd be very easy to make the exact same effect using a simple program like Adobe After Effects.
TedStixon