The Japanese film Carved: A Slit-Mouthed Woman (2007; original title, Kuchisake-onna) is an example of what happens when two horror subgenres mix. You get a new brew, which either brings new horror potential or degenerates into horror slop. The Evil Dead, for example, successfully mixed the demon and zombie films, whereas Jason X made horror slop out of mixing the slasher and space horror films.
In the case of Carved, one of the two subgenres undergoing mixture is that of the angry ghost. A staple of J-horror, familiar from such films as the original Japanese versions of The Ring and Dark Water, the angry ghost harbors some kind of grudge against the living, and either kills them or makes their lives miserable until resolution is found. The other subgenre, associated principally with American horror, is the slasher, an individual, usually masked or deformed, who wields a sharp instrument against a series of victims and is notoriously hard to kill. Examples include Halloween, Friday the 13th, A Nightmare on Elm Street, and on and on.
Carved condenses these two figures--the angry ghost and the slasher--into a single deformed destructive being, the slit-mouthed woman. The slit-mouthed woman, we learn in the course of the movie, was a child abuser who, in a struggle with one of her children, had her mouth slit open from ear to ear. After her death, she lives on in ghostly form, appearing as a woman in a raincoat with a hospital mask hiding her scars. She carries a big pair of scissors, abducts children one at a time, and mutilates or kills them. She is thus both an angry ghost and a slasher.
Carved is fairly effective in its merging of the two subgenres, combining the creepiness of the angry ghost story with the visceral shocks of the slasher story. The abundance of kidjep (kids in jeopardy) makes it somewhat unpleasant, especially when one child gets her face slashed in slit-mouthed style, but the movie puts some thought behind this. In several families presented in the story, mothers are abusive to their children, raising the spectre of a world in which children are at the mercy of their parents--which, after all, they are.
Carved is less successful on other fronts, such as maintaining interest in the two boring teachers who are pursuing the slit-mouthed woman, and in making sense of such plot elements as the slit-mouthed woman's possession of other mothers. Somehow, when you try to kill the slit-mouthed woman, you actually kill some other woman whom the angry ghost has possessed but whom you didn't notice before. How? I don't know. Still, overall, Carved does a nice job of welding its subgenres.
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