Mark’s Down On Your Syntax said:

I seem to remember reading somewhere that the plan was to make the Halloween movies an anthology, but after the third one didn’t do much business they scrapped that idea and went back to Michael Myers (and apparently felt the need to remind people he was in it by including his name in every title!) It’s a shame really because Season of the Witch was fun and creepy.

This is all true, except that it wasn’t the same “They” that made 4 and on. After 3, John Carpenter scrapped all ideas and sold the franchise to… um… whatshisname and he’s made tons of crappy Myers movies since.

Also, Part 4 would have been a sequel to 3. It would have been an anthology of cliffhangers and resolutions. Awesome idea.

JEDIT: “whatshisname” is Moustapha Akkad.