Yeong-hye is, in her husband’s opening words, “completely unremarkable in every way”. She is a reasonably diligent homemaker, a reasonably attentive spouse, not deeply unhappy and driven by no great passions. Her husband, Mr Cheong, is a mediocre employee, not greatly ambitious, mildly unenthused by his life but not dramatically so. Time ticks by, and the two of them get on with living their ordinary lives; but their ordinariness, it turns out, is more fragile than they realise.

Things begin to fracture the day Yeong-hye throws away all the meat from the freezer and announces that henceforth she is going to be a vegetarian. The only explanation she gives her husband is not hugely satisfactory: “I had a dream.” We know, though her husband doesn’t, something of the nature of the dream: it is dark, bloody and aggressive. Violence soon breaks out in Yeong-hye’s waking world, too, when her father tries to force a piece of sweet-and-sour pork into her mouth, and in revolt she stabs herself.

And it goes downhill from there. Other people are dragged in, other relationships fray and Yeong-hye’s vow to remain vegetarian is the one constant in a family disintegrating before our eyes. Her husband is frustrated at this complication in his meticulously uncomplicated life, and can’t help thinking it’s all about him. (What happens when they have to go to dinner with his boss? And his wife not even wearing a bra any more! What will people think?) Her sister, In-hye, struggles with her sense of familial responsibility, while learning that, even when a family member is in trouble, there is only so much others can do.

The Vegetarian is a story in three acts: the first shows us Yeong-hye’s decision and her family’s reaction; the second focuses on her brother-in-law, an unsuccessful artist who becomes obsessed with her body; the third on In-hye, the manager of a cosmetics store, trying to find her own way of dealing with the fallout from the family collapse. Across the three parts, we are pressed up against a society’s most inflexible structures – expectations of behaviour, the workings of institutions – and we watch them fail one by one. The novel repeatedly shows the frictions between huge passion and chilling detachment, between desires that are fed and those that are denied. With such violence in these characters’ internal worlds, and such a maddening external impassiveness, those inner passions are bound to break out somehow, and it won’t be pretty.

This is Han Kang’s first novel to appear in English, and it’s a bracing, visceral, system-shocking addition to the Anglophone reader’s diet. It is sensual, provocative and violent, ripe with potent images, startling colours and disturbing questions. As Yeong-hye changes, the book’s language shifts, too, with Deborah Smith’s translation moving between the baffled irritation of Mr Cheong’s first-person narration in part one, the measured prose of In-hye’s world, the dense and bloody narrative of Yeong-hye’s dreams, and seductive descriptions of living bodies painted with flowers, in states of transformation or wasting away. Sentence by sentence, The Vegetarian is an extraordinary experience. Last year’s London Book Fair had Korea as guest of honour, in the hope of tempting English-language publishers to seek out more contemporary Korean novelists, but The Vegetarian will be hard to beat.

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