The Stepford Wives (1974)
"Something strange is happening in the town of Stepford"
Upon the recommendation—indeed, the insistence—of a friend with tastes similar to my own, I tracked down and watched the original 1974 version of The Stepford Wives. As far as I can remember, I had never seen it before. However, having read the novel by Ira Levin, many years ago, I was more or less familiar with the story. Indeed, I was of the opinion that everbody must know the Stepford story—but despite that, I shall not post any unprotected spoilers. (I've had a few films spoiled because the person posting thought "everybody must have seen this by now", and it's just so difficult to unread something once you've read it...)