All change: everything metamorphoses in Aquarium, including its author, who takes on the persona of a 12-year-old girl

Books ought to be able to stand on their own, but perhaps it is important to know this about David Vann: a year after his stepmother’s mother had shot her husband and herself, his father also shot himself. Vann was 13 years old. The reason it’s important to know this is that what might seem implausible in the author’s new novel, Aquarium, probably does not at all seem like that to him.

Vann has mined these events for his writing. The second tragedy he treated in his first, much acclaimed, book, Legend of a Suicide (2008), a hybrid work containing bits of all sorts of genre, but concerned chiefly with a son’s relationship with his father. Subsequent novels, and Aquarium too, deal with the same subject, variations on a theme: the relationship between parent and child.

The earlier books were set in Alaska, where Vann was born; Aquarium moves further south, to Seattle, but the weather remains grey, rainy, cold. The narrator never neglects to tell us what the weather is like, although she (yes, see below) tends, irritatingly, to do it in the manner of a screenwriter, free of verb or article: ‘Slow morning, grey and watery light, sound of rain.’

The weather, then, sets the tone. Horizons are short, the world of the characters confined, like a fish tank. If deprivation was to Larkin what daffodils were to Wordsworth, then David Vann’s daffodils are fish. They figure here in all their metaphorical glory to an even greater extent than in Legend of a Suicide.

Told, bravely but persuasively, from the point of view of Caitlin, an older woman channelling her sexually awakening 12-year-old self, much of the first third of the book is set at an aquarium where she waits for her mother after school. It is here she meets an old man who seems to have a fascination for the fish equal to her own. Who he turns out to be, and his developing relationship with the narrator and her mother, are the lines that bring the story home.

There is a question asked towards the end of the book that provides a kind of key to its understanding: ‘How do we know how to trust any form?’ This word, ‘form’, recurs, along with ‘pattern’ and ‘shape’. The reason it is difficult to trust any form is that forms, most terribly human forms, change. Everything metamorphoses. The old man has several shapes, Caitlin physically changes into a sexual creature, her mother more or less shape-shifts and the mother’s lover turns out to be not quite what we thought. Homes change.

Fairy tale intrudes — voices are mimicked and snowmen live. And while the fish are anthropomorphised, the humans are pescomorphed: ‘Be a barnacle,’ her mother orders Caitlin at one point. Artichoke hearts on a pizza are ‘like jellyfish’.

I am anxious not to give away plot details because the story depends on surprise (what you might call sudden change) for much of its drive, but, be assured, you’ll keep wanting to know what happens next. The author has metamorphosed himself into a 12-year-old girl with startlingly brilliant results. Aquarium is as rich as good poetry and as addictive as a first-class detective novel.