Westworld (1973) or The Stepford Wives (1975)?
Wikipedia says Michael Crichton wrote the screenplay for Westworld August 1972, and Ira Levin's The Stepford Wives was published September 1972.
I say The Stepford Wives is the better story.
Agreed. WW is a fine script full of believable dialogue and "advanced" technical jargon that to its credit didn't even make my BS detectors blip, but the story is fairly simple compared to TSW. As movies, while WW certainly shows its age more, both films succeed admirably as horror/sci-fi and they both rate an easy 7/10 in my book, with TSW maybe edging closer to 7.5.
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