Has just been remade!
I apologize if this has already been discussed. This movie has just been remade and according to IMDB is scheduled to be released sometime in 2010.
The new version was co-written by Guillermo del Toro (Pan's Labyrinth) and Matthew Robbins (Dragon Slayer).
This time the Kim Darby character is a young girl instead. Potentially makes the premise even scarier and more suspenseful since it's a kid. Also makes any poor judgement on the protagonist's part much more forgivable. I hate it when horror movie character's are in danger because of their own stupidity.
This movie scared the heck out of me as a little kid. I can't believe my parents let me watch it. I think I saw it on one of those old afternoon movie shows they used to show back in the 1970's.
According to the trivia about the original on IMDB: "The total time of filming, including script approval by Lorimar, casting, special effects, voice-over and exterior shots were all completed in slightly over two weeks, one of the quickest made-for-television movies ever made; this was due mainly to a writers strike that had begun just before the script was completed."
So I can see why this wasn't the greatest quality movie of the week in some ways, still, it really stuck with me. It was a great concept for a scary movie. They just didn't have the time to execute it better but it still had impact. And, after all, it WAS a 1970's t.v. movie of week.