Mbwun, from The Relic. Peter Hyams' terrible movie does absolutely no justice to the marvelous 1997 novel by Douglas Preston and Lincoln Child. Taking a cue from the "techno-thriller" genre that exploded in the wake of Jurassic Park, The Relic combines genetic mutation with the mysteries of the Amazon to introduce an unstoppable creature with an addiction to the human hypothalamus. That most of the book's action takes place among the mummified wonders and forgotten warrens of New York City's Museum of Natural History only adds to the creepy factor.
The Monster, from The Host. This 2006 Korean cult-hit features one of the most unique-looking baddies in recent memory. The film's plot implies the monster is a product of toxic waste, and the creature definitely has the appearance of evolution gone horrible wrong. Like many classic monster movies, The Host builds a certain amount of sympathy for an animal that is, after all, just doing its thing, and works in plenty of laughs to go with its big heart. It would be a great flick with a less imaginative creature, but having something so weird that it's actually hard to look at really takes it over the top.
The Plant, from The Ruins. Another inventive and genuinely scary novel that got screwed in the adaptation to film. Scott Smith's book not only serves up a terrifying new threat, but also deftly weaves in the factors of isolation and exposure to the elements, and how they can quickly fray the fabric of friendship. Like Night of the Living Dead before it, The Ruins doesn't waste a lot of time explaining its antagonist — which may not be what it seems at all — and in the end, it doesn't matter. The novel's incredibly creative "monster" forms a mesmerizing hook for a story that is, more than anything, about people falling apart under pressure.
The Babies, from "Croatoan." Harlan Ellison's short stories have never been short on imagination, but 1975's "Croatoan" is probably the most baldly unsettling tale he's ever penned. In it, a young man who has just coerced his pregnant lover into an abortion is goaded by her hysterics into the sewers under the city to retrieve the fetus. (It was an at-home procedure.) Under the streets, he finds that those disposed-of unborn children haven't died at all; they have survived, and even developed what passes for a society ... a society in need of a leader. A father figure, if you will, heh heh.
HAL 9000, from 2001: A Space Odyssey. Every story of technology gone murderously wrong owes a debt to what's not really a horror movie at all — at least, not on the surface. People have argued for years that most of director Stanley Kubrick's films are, at their heart, horror flicks, and there's a lot of evidence to support the theory. HAL's descent into disturbingly human madness is indeed horrific; what's even scarier is the fact that 2001 never seems to age, and in fact appears more and more relevant as time passes. In any case, that HAL is a masterwork of vision and terror — and, in its time, a "new monster" — is beyond debate.