>>11853221
NTA, but Rosemary's Baby is the closest thing I can think of, though there is a lot of cult horror media I haven't yet been exposed to.
I browsed the wiki for a bit trying to see if anything jumped out at me, and didn't see anything particular about the cult. But since I very much like the Andrew Wyeth painting "Christina's World", I was surprised to see this connection on the wiki: the Gillespie house is clearly inspired by Christina's house in the painting.