This is what can happen to you, if you read H.P. Lovecraft at bedtime.
I was reading his story, The Lurking Fear, about a family of Dutch settlers in New York who, through isolation and inbreeding, had degenerated into monsters, evolved backwards into a tribe of cannibalistic apes. Lovecraft was a great believer in the Settled Science of his time. Pure poppycock, but it was his art to scare you with it anyway.
That night I dreamed I had to visit a certain city in New Jersey, and when I went to drive home, I took a wrong turn and wound up driving deeper and deeper into the city, unable to find a road that led out. The streets got narrower and narrower, the buildings higher and higher, many of them shabby and poorly maintained. And the people I saw on the sidewalks, the deeper I got into the city, the more off-kilter they looked: something not quite right about them.
At last I had to stop my car for a red light, right in front of a brick building with an open roll-up door, like that of a garage. In the doorway loitered some individuals who were definitely on their way to becoming creatures in a Lovecraft story: half-human, half-beast, the worst half of both.
These gawked at me in a way I didn’t like at all.
Then the light turned green. And my car’s engine died.
And the loiterers moved in my direction…
You bet your boots I woke up! No way I was gonna stick around for the rest. I told my wife about it and she said the dream would make a pretty good horror story, and an even better start for a horror movie.
I do use a lot of dream material in my books, but I think I’ll leave this one to H.P. Lovecraft.