Back in the 1970s when I was still in high school I had a subscription to the Science Fiction Book Club. I’m trying now to locate a short story from that time.
The story tells of a group of people who take a drug (I think it was called Skyy) that would make time seem to pass extremely slowly. They would then skydive together, experiencing it as a gentle weightless floating instead of a free fall.
The story ends in tragedy as they become so used to the slowness that they neglect to deploy their parachutes.
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