Apparently there is a three-hour cut of Needful Things that director Fraser C. Heston put together for TNT, which includes nearly an hour's worth of deleted scenes but also has been sanitized for television, with profanity and violence toned down. On the IMDb comment boards for this movie, someone notes a bootleg version with the TV cut and the theatrical cut stitched together in order to maximize both R-rated content and additional footage. There's clearly a very obsessive (if also very small) cult around this film, which is strange given that it comes off like a halfway effective adaptation of one of Stephen King's more bloated novels. I found a lot of it to be pretty entertaining, but I definitely wouldn't have wanted it to be an hour longer.
Part of the movie's strength is actually the way that it streamlines King's sprawling story and cuts out a whole bunch of minor characters. A TV miniseries version would have explored every little digression in the novel, but a movie should be more focused and condensed, and that's exactly what happens here. We have the hero (Ed Harris as small-town cop Alan Pangborn), the villain (Max Von Sydow as evil shopkeeper Leland Gaunt), the love interest (Bonnie Bedelia as Alan's fiancee) and a few supporting characters to illustrate the premise. That's all we need, especially since King's novel, which is billed as "the last Castle Rock story," relies heavily on background for character and setting from other books, which the movie doesn't have. Heston and writer W.D. Richter take just enough to tell the story, and throw out the rest (or at least relegate it to the extended cut).
Some of the stuff here is a little awkward, and the movie's climax relies too much on big explosions and a convenient speech that seems to erase all the complicated animosities between characters. Harris is a little bland as the crusading Alan, who seems to have no flaws, but Von Sydow is predictably strong as the devious Gaunt, who uses people's greatest desires to prod them into evil acts. J.T. Walsh hams it up as a paranoid local politician, but his performance works well as a depiction of the descent into complete madness and paranoia. Heston could have gone a little deeper, not by adding extra subplots but by exploring the themes more thoroughly, but his approach is entertaining enough, and the running time is just right.
How far to Castle Rock: As mentioned above, Needful Things is a key Castle Rock novel (although of course it wasn't really King's last Castle Rock story), and the movie takes place there as well. The character of Alan Pangborn was played just a few months earlier by Michael Rooker in The Dark Half, but the movie ignores connections to other King stories (even omitting the major character of Ace Merrill, played by Kiefer Sutherland in Stand By Me).