To say that it is long-awaited hardly does it justice. For more than 30 years the last book written by Vladimir Nabokov sat in the vaults of a Swiss bank, seemingly destined to gather dust for all time.

Before he died in 1977, the author said that he wanted it to be burnt, and his son and literary executor, Dmitri, said that it would remain unpublished. As first reported by The Times in May last year, he relented. Today The Times Magazine publishes the world’s first official extract from The Original of Laura, “a novel in fragments”.

The description is a fitting one because, following Nabokov’s usual practice, the novel was written in pencil on 138 index cards. Dmitri Nabokov, 75, said: “I had to traverse a stifling barrier of pain before touching the cards he had lovingly arranged.” What he found he described as “an embryonic masterpiece whose pockets of genius were just beginning to pupate here and there on his ever-present index cards”.

Before the author of Lolita and Pale Fire died, he made his wife, Véra, promise that she would throw the novel on the fire. She could not bring herself to do it and after she died the decision passed to their son.

For years he was torn between duty to his father and what he saw as the demands of posterity. As recently as 2005 he let the journalist and author Ron Rosenbaum know that he would “probably destroy Laura”.

In the end, he explains in the introduction, it was the influence of his father from beyond the grave that helped him to decide in favour of publishing. “I have said and written more than once that, to me, my parents, in a sense, had never died, but lived on, looking over my shoulder in a kind of virtual limbo, able to offer a thought or counsel in order to assist me in a vital decision, were it a crucial mot juste or some more mundane concern. If it pleases an imaginative commentator to liken the case to mystical phenomena, so be it.”

Alexis Kirschbaum, the Penguin Classics editor, who bought the book and continuing rights to the Nabokov backlist in a six-figure deal, went to Mr Nabokov’s home in Montreux to cement the purchase. Mr Nabokov, who suffered “a bad spell of pneumonia” that left him in a coma last spring, said that doctors told him “I was destined for the grave myself”.

The thought prompted further comment on how his father might have given him posthumous guidance. In an e-mail to an Australian television programme, he said: “My father, with a wry and fond smile, might well have contradicted himself upon seeing me in my present situation and said, ‘Well, why don’t you mix the useful with the pleasurable? That is, say or do what you like, but why not make some money on the damn thing?’.”

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