Hobie takes Theo under his wing, an act of kindness he will both cherish and live to regret, and teaches him the basics of his trade. Theo is spellbound by the confusion of imitation and originality, truth and lies, old and new. Hobie teaches him that perfectionism in restoration requires flaws to be included: "Anything too worn was a dead giveaway," Theo notes. "Real age … was variable, crooked, capricious, singing here, and sullen there."

Theo could be describing himself, or even as a whole, whose knowingly forensic attention to minutiae imitates Hobie's painstaking labours to update "ancients and honorables", working "by hand like one of the old masters". The seeds of this exploration is proposed by Tartt's title, which was inspired by another artwork: Carel Fabritius' painting of the same name, a mini-masterpiece whose fusion of hyper-realism and trompe l'oeil blurs some serious lines between art and life, past and present: "A power and shine came off it," Theo notes lovingly, "that rendered everything sharp-edged and yet more tender and lovely than it actually was, and lovelier still because it was a part of the past, and irretrievable."

Tartt's attempts something similar, but does so by expanding Fabritius' canvas a few trillion per cent. Whereas the painting is modest (Fabritius' bird is no bigger than, well, a goldfinch), the novel is vast at 771 pages. Somehow, despite its scale, this extraordinary work manages to remain intensely intimate, thanks largely to Tartt's microscopic powers of description. exults in using three adjectives where one might suffice. The effect in the opening pages is challenging but oddly gripping, as if fictional time has slowed to that of real life itself - an homage, perhaps, to Fabritius' goldfinch, which imitates reality in scale, shape and colour, but is irrevocably contrived.

The novel progresses by exploring how matters of a moment unfurl unpredictably over time. For 13-year-old Theo, this begins with an explosion: a terrorist bomb destroys a wing of a New York museum. The device deftly reminds us of Fabritius' own death almost four centuries before, setting in place what Theo later describes as a "dreamlike mangle of past and present". Tartt's forensic prose is intent on tracing the unforeseeable consequences of this blast - not only for the characters who were present, but those yet to appear.

Theo and his mother arrive in front of Fabritius' masterpiece just in time for the detonation. Theo miraculously survives, his mother dies. Disorientated, he crawls through the rubble, comforts a dying elderly man, who passes him a ring and Fabritius' priceless painting, which he removes and keeps.

Tartt is brilliant at portraying how young lives are vulnerable to sudden shocks, and especially to loved ones' sudden death. Almost every teenager has suffered loss of one form or another. The prevalence of de facto orphans is fitting for a novel that self-consciously echoes the realist novels of the 19th century: Theo's convoluted journey towards adulthood contains hints of and a remixed . There are erratic, violent fathers, kindly paternal surrogates, stern but caring lawyers, wild but loyal best friends, and competing love interests blessed with different Dickensian ideals.

Tartt isn't pastiching the realist novel so much as updating it for our times. Her version is filtered through existentialism, the Beats, and Frank O'Hara's closely observed verse. Like Hobie's carefully restored antiques, the resulting hybrid skirts originality and imitation, confuses what is genuine and fake. Tartt shines a neon light on all this during a wonderful, wild section in Las Vegas. Here even magic is an illusion: Theo is recast as Harry Potter by his friend Boris, neither quite realising they are really Rimbaud and Verlaine.

Like Fabritius, Tartt's daring conceit is to create a work of art that strives to be realistic, but knows that the harder it tries, the more its contrivances are exposed to view. teases with its own artifice: Theo's mother is a model who takes a bad photograph; his temporary foster family stage themselves like Broadway plays; Tartt puns repeatedly on the word "picture".

This self-consciousness isn't empty meta-fiction any more than Theo is a postmodern, unreliable narrator. Instead, his close reading of reality enacts the gradual revelations of his unspoken story. Initially, we take it on faith that he's a bright kid with a keen eye and vivid imagination. But gradually, holes in his narration begin to appear. Who is Jerome? Why has Theo failed to mention his drug dependence? And what is all that detail covering up?

The slow accumulation of Tartt's obsessive narration is Theo's way of coping with, or avoiding pain. He concentrates on the small stuff to evade the big picture.

In this, the novel becomes profoundly moving. asks how humans facing the "fundamental chaos and uncertainty of the world" restore themselves after loss. By burying problems, or by searching for the sustaining consolations of love, art and friendship? Can people, like objects, be made as good as new, to quote Hobie?

These meditations contend with other questions. How do we measure value in a material world where reality and representation are almost indivisible? ("An object - any object - was worth whatever you could get somebody to pay for it.") How do we take responsibility for our actions when cause and effect seem ever more random and unfathomable? As one character observes: "The moral of the story is, who knows where it will all take you?"

At a time when so much literature is either contemptuous of plot or enslaved by it, deadened by prose from the creative writing course or genre utilitarianism, is a gripping page-turner and a challenging, beautifully written account of modern life. Moving but unsentimental, funny without being trite, all human life is here. Or at least, quite a lot. will doubtless be a contender for one of 2013's best novels. It deserves to be read for many years to come.