|Male gharial. Image: Wikipedia Commons.|
In my opinion, horror only works when the reader (or viewer) can see themselves in the story. This has been the downfall of sci-fi, in particular. It usually takes place so far in the future that people can't relate. In my books, I try to avoid this pitfall.
For another thing, horror has to be possible. And that means it must be based on real life. As an example, let's use a movie rather than a book (I do this because we've all seen the same movies; not so with books). The reason why "Alien" is such a scary movie is that its premise is reality-based. Placing your young inside a body to gestate? Wasps do this every day, and pity the poor caterpillars into which they thrust their babies. They eat their way out -- just like in "Alien". And those jaws that contain so many teeth in a long, almost tube-like structure? Look at a gharial. It's the same mouth and teeth that we see in "Alien" (though the gharial's teeth are external). So "Alien" is based on things we already know from real life. Something inside you says, "this could really happen!" That's why it's scary.
What are you looking for when you pick up a horror or sci-fi novel? Let me know. And if you've read "Xmas Carol", please consider commenting and telling me (and others) what you thought of the book.
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