Natalie Haynes: It's not a horror film if it isn't actually scary

The thing is I like a good horror film, and there aren't enough of them about at the moment. I like horror that genuinely scares me: The Haunting, for example gave me the major wig as a child, and I still won't live in a creaky house. I like vampires and zombies and werewolves and ghosts, and yet I can't remember the last time I was scared at the cinema (other than when a mouse ran over my foot one time. Which will teach me to wear flip flops in a dark room carpeted entirely with nachos and fizzy pop). Maybe during Drag Me To Hell, the climax of which features a particularly alarming goat.

So am I glad to hear there's a horror film, Human Centipede II, coming up, so ghastly that it won't be shown – legally – in the UK? Sadly not. This is because I have seen the first Human Centipede film – don't judge me, I was reviewing torture porn that week for Radio 3. Actually, having read that sentence back, do judge me. I deserve it.

Human Centipede plays on the gross-out end of the horror market, as does most horror produced now – like the Saw franchise, and Hostel films. Rather than asking the audience the question of how they would survive the ghostly attacker, the demon let loose on the streets, or the chainsaw-wielding nutcase, it asks them if they'd rather have a hand crushed or be sliced open by a pendulum. Since I think most of us would answer with a resounding, "Neither", it's hard to see where the suspense lies.

Perversely, the harder these films try to shock, the less the suspense: it just becomes a catalogue of ick. And that makes it difficult to stay emotionally engaged enough to be afraid. Human Centipede plays on a previously little-considered fear of compulsory coprophilia, which is disgusting, sure, but not frightening. The plot of Human Centipede II apparently centres on a sexual sadist who becomes obsessed with a DVD copy of the first movie. Chance would be a fine thing – I was being paid to watch it, and I still dozed off in the middle. It's a movie that climaxes long before it ends, and you can't even go and get popcorn to cheer yourself up, as your pervading response isn't crippling terror, but vague nausea. And no one ever heard a creak on the stairs in the middle of the night and was paralysed by the fear of feeling a bit queasy. It's surely time horror became horrifying again, and not just gross.