Zadie Smith has spent a long time concertedly not writing historical fiction. Determined to stay in the present, she has been on guard against the lures of the past. But history got her in the end, calling her down a grassy track to a Victorian village called Willesden. Thank goodness: we need minds like hers on the job. The Fraud, her sixth novel, is partly about an enslaved man on a Jamaican sugar plantation, and it’s a comedy: those two things at once. Few would dare; fewer could pull it off as Smith does here, mixing narrative delight with a vein of rapid, skimming satire as she sketches scenes of life in 19th-century England and the Caribbean. The novel is a complicated mosaic of episodes from interleaved plots. Much of it follows a bizarre court case, “a tragicomedy of obscene length”, that gripped the British public in the 1870s. Sir Roger Tichborne, heir to a baronetcy and a fortune, was thought to have been lost at sea, but a cockney-born butcher in Australia declared himself to be the living Sir Roger and set out to London to prove his identity. The hearings extended over years. In parlours across England, evening newspapers were scoured for Tichborne developments. We cross the threshold into one particular household, the home of the real-life novelist William Ainsworth, his young wife Sarah, and the woman who has shared her life with him over 40 years: Eliza Touchet. The historical Eliza is known only from a few letters and scrapbooks, and the copy of A Christmas Carol that Dickens signed to her. Surveying the shape of the gap, its spaciousness and possibility, Smith has made her up. The queer lover of a long-mourned woman; the male novelist’s muse, his housekeeper, his friend and intellectual partner; the pitied or puzzled-over “third wheel” in other people’s marriages; Catholic, abolitionist, writer. “What would it be like to have a name for all these various people and urges within herself? But Mrs Touchet was her name!” Eliza’s long relationship with Ainsworth is beautifully observed, its joys shining amid the cartoon absurdities of managing a Great Man. Smith has a high time with Ainsworth, author of 41 forgotten novels, purveyor of preposterous plots and archaic language that no one ever used. Muskets, laces, witches, livid lightning: sceptical Eliza skims enough of his latest offering to deliver the necessary praise (“‘A triumph!’ she ejaculated”) but she finds it all unreadable. Reflecting sadly on William’s preoccupation with “the distant, storied past”, she regrets his lack of attention to “the kinds of stories that were right in front of him”. Ainsworth works on what he calls his “Jamaica novel”, though it features nothing Jamaican until a paragraph at the end vaguely evokes “long savannahs fringed with groves of cocoa trees”. Smith notes the inadequacy and does better. The prime witness in the trial, staunch supporter of the “Tichborne Claimant”, was an ageing Black man named Andrew Bogle who had spent most of his life as valet to an earlier Tichborne. His restrained testimony survives in court transcripts. But there was more to Bogle than being a servant of Tichbornes. What unspoken experiences have brought him to this witness box? It’s Eliza who takes him to a chophouse and asks. Smith devotes most of the second half of her book to a version of Bogle’s history, reaching back into the 1770s when his father was a boy, newly arrived on Hope Plantation. It’s a story of family inheritance and parenthood, agony and loss. We hear the voice of enslaved Johanna after months on the treadmill, and the silence of Bogle in Dorset in the 1830s, feeling a “well-fed fraud”, screaming only in his dreams. This book within the book might stand alone. But in all her novels, Smith refuses single trajectories and central heroes. Here, in glimpses and panoramas, she finds the meshing fibres of the world that link Bogle with the eminent Victorian novelist writing romances, with the Stepney woman cheering an impostor in a courtroom, and with Eliza. The Fraud deals in patterns of juxtaposition, in foils and reflections. It might be the holes that keep opening in the sturdy fabric of Victorian social life, or the routine travesties of justice perpetrated in Kingston while Londoners are absorbed in the minutiae of Tichborne. The rumblings of connection can be most powerful when only obscurely perceived. On one page: the grief and fury of Bogle, waiting at table while his white masters discuss the catastrophic burning of a slave village. A page earlier: Eliza’s astonished feeling of exclusion as a young Black man and woman turn away from her to carry on conversations of their own. In all this multiplicity, different models of Victorian fiction are inherited and transformed. Being tugged away from Eliza is not unlike being tugged from Dorothea Brooke to consider the other inhabitants of Middlemarch. As it happens, Eliza is reading that very novel. In a priceless momentary exchange, William frowns at her peculiar interest in “a lot of people going about their lives in a village”. “I like it,” says Eliza contentedly, seeing no reason to explain. As for Dickens, there’s no avoiding him. “He was everywhere, like a miasma.” He’s there at Eliza’s literary dinners; he’s there when anyone tries to describe street children or lawyers. Smith keeps up a splendidly exasperated satire on her omnipresent forebear. She also gets free of him. Dickens did not write Bogle’s story. The Fraud is a curious combination of gloriously light, deft writing and strenuous construction. There’s a risk of readerly bafflement as bright shards of narrative are shaken into unpredictable combinations across time and place. But the novel’s hybridity becomes part of its fascination. It slows and expands lavishly in honour of its Victorian subjects, yet its chapters are elliptical half-scenes chosen with modernist economy. Happily its eight “volumes” can be bound with one spine. Here is historical fiction with all the day-lit attentiveness that Eliza hopes for: “stories of human beings, struggling, suffering, deluding others and themselves, being cruel to each other and kind. Usually both.” Generous and undogmatic as ever, Smith makes room for “both”. The Fraud by Zadie Smith is published by Hamish Hamilton (£20). 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