I had a thought strike me yesterday (no it didn’t hurt, but it is very lonely and soooo, soooo cold). To whit, the thing that makes horror really scary is mystery.
The minute we fully understand that which is scary, it ceases to be as scary. Typically when there’s a big reveal in a horror novel or a movie all the scary evaporates and it becomes a thriller or an action adventure (or sometimes just plain silly). For example, I give you vampires. It’s really difficult to make them scary because now we “know” all of their weakness. Once the protagonists know that there are vampires they just break out the stakes and boom.
Now you could argue that you can still make a story scary by keeping the protagonists ignorant. If they don’t know about or don’t believe in bogey monsters then they can’t fight them as effectively. That can indeed help, but only a bit. We, the audience still know and that can neuter the story.
Another example, this one from the movies. Pick your modern horror icons: Jason, Freddy, Michael. What makes them scary at least in large part is, we don’t know what they are or how to put them down. They’re unstoppable forces, until… someone figures out their weakness or what precisely they are.
Now that’s not to say you can’t make these things scary or at least interesting. The thing is, I’m not so sure I’m talented enough to do that yet. It’s okay, most storytellers in the horror genre aren’t either. For the most part they just do what’s become popular and throw a lot of gore at it and hope it sticks. Some of them are gutsy enough to try and re-invent the critter. Rob Zombie’s given that a number of shots. I won’t opine on how successful he’s been since I haven’t seen most of them, but that is one option.
The better thing? Create something new, out of whole cloth. Don’t give away all (or any) of your creation’s secrets. maintain that aura of mystery. ‘Cause once you’ve shown it all, it’s just “Speed” in a haunted house