People look out their windows, and see hundreds of lawn gnomes... On lawns. But there is something odd about them. For one thing, there usually aren't that many gnomes. And these gnomes don't look normal. If you asked anyone, they would tell you "Of course they look normal! They're gnomes!" But everyone is hiding what is really on their mind. They've got a certain air of... seething about them. Like they have vague notions about having you sliced up into tiny bits. But not in so many words, gnomes aren't very cognitive.
And they move. Well, they don't move. They do both. When you look at them, they just sit there, like you would expect. But sometimes, when you aren't looking, and late at night, you can just sense that they are moving. You don't know it, but you do. And they make strange grunting noises. While simultaneously not grunting, gnomes don't grunt, you know that. And when you look out the window in the morning, they are different. I mean, they look the same, but you think that one over there has moved an inch to the left. No, you are sure that one there wasn't there yesterday! Or was it? They all look the same. And they are all evil. But that's just silly, isn't it? How can something that isn't alive be evil.
You go outside and kick a few over. Big mistake, you realize, but it's too late. They are just gnomes. But you can't get the feeling out of your head. They aren't just gnomes. They are evil gnomes.