Mistaken, by Neil Jordan, John Murray, RRP£18.99, 320 pages

Kevin Thunder grows up on the Northside of Dublin in the 1960s, in a modest house that stands out “like a rotten tooth” beside the gentrified stucco properties all around. Located next door to the house Bram Stoker inhabited, Kevin’s home as well as his thoughts and dreams are haunted by the spectre of Dracula, sometimes envisioned as a man in a flapping cloak, sometimes as a squalid local paedophile.

Kevin’s closeness to his lovely mother, whom he accompanies on romantic swimming trips to the sea – until it becomes too embarrassing – is very tenderly drawn. While she swims he watches over her clothes, “the neatly folded stockings, the cream white girdle”. His bookie father is unsatisfactory, shadowy, often absent at distant racecourses. His mother’s relationships with the lodgers in his house make Kevin wonder about her deeper allegiances too. Like many a thoughtful adolescent Kevin does not feel quite right inside. He is full of yearning for he knows not what, yet this is no ordinary dislocation. Even “the idea of home”, to Kevin, is a “kind of longing”.

Kevin has a double in the more refined spaces of Palmerston Park on the Southside, a boy named Gerald Spain who resembles him so thoroughly in looks, scent and aura that they are frequently mistaken for each other. Girls reproach Kevin for abandoning them, or exclaim to him mid-clinch, “You’ve never done that before!” Shopkeepers remind him that he’s not to darken their doorways again, not after last time. Baffled at first, when he actually meets Gerald he is moved by and soon in thrall to his double. Gerald’s existence somehow makes sense and justifies, distinguishes even, the sense of unease Kevin has felt all his life. The realisation that there is someone else experiencing his pain and his joy, providing an extra layer to his life, fuels a powerful connection between Kevin and his doppelgänger. It is a kind of love.

As the boys’ lives progress through adolescence and adulthood the pair become more caught up with each other, their relationship veering from the symbiotic to the parasitic and back again, via rivalry, violence and love. Kevin craves his double’s company, envies him his more solid-seeming state, while Gerald envies Kevin his worldly ways. When Gerald’s literary career is launched under the pen-name Kevin Thunder, Kevin reads Gerald’s poems and stories, utterly rapt. What clues will they provide to the man he knows better than himself? When Gerald’s pregnant New York mistress threatens to ruin his marriage, Gerald asks Kevin to intervene on his behalf. Is he really requiring that Kevin steps into his shoes, that he seduces the woman in Gerald’s place and raises the child as his own so Gerald can return to his wife and daughter, conscience clear?

Told in part through Kevin’s friendship with Emily, Gerald’s grown-up daughter, Mistaken is written with great skill, confidence and vim. Though built on a tower of bold improbabilities – to put it mildly – this novel is utterly convincing: full of subtlety, delicate, piercing prose, charming, lively dialogue and descriptive passages that are poetic, witty and acute. At times it has the pace of a thriller, yet for all its highly specific subject matter it still manages to achieve a feeling of spaciousness in which it is possible for the writer to ponder, with a bit of leisure, the definition of human nature.

This is not a flawless novel: the names Kevin Thunder and Gerald Spain strike me as spectacularly bad. What was the author thinking? The prose is so winning that you forgive all the coincidences – that is, until they start being explained away rather quickly in the last quarter of the book. Yet taken as a whole Mistaken is a fine achievement, a powerful, involving and beautifully written book about identity and loss.

Susie Boyt is an FT columnist

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