Emma Brown by Clare Boylan

Charlotte Brontë's fiction has attracted a range of literary meddling. Charlotte Cory enjoys a vivacious and witty expansion of a fragment

When Charlotte Brontë died in 1855, she left two chapters of an unfinished novel, Emma. Thackeray published these five years later in his new Cornhill Magazine, together with a fulsome introduction in which he speculated on the masterpiece that fans of Jane Eyre had been deprived of by Brontë's early death: "As I read this little fragmentary sketch, I think of the rest. Is it? And where is it? Will not the leaf be turned some day, and the story be told?"

A few months before her death, Charlotte had whiled away a winter evening by reading the work to her husband, Arthur Bell Nicholls. When she finished, he remarked: "The critics will accuse you of repetition." She replied: "Oh, I shall alter that. I always begin two or three times before I can please myself." As Thackeray says: "It was not to be. The trembling little hand was to write no more. The heart newly awakened to love and happiness and throbbing with maternal hope was soon to cease to beat ..."

Critics often cite this account to berate Bell Nicholls for discouraging his wife's writing. The poor man (mindful of the many schools and orphans in her fictions) probably did not know what to say. The two extant chapters involving a rich heiress who turns out to be an imposter are delightfully gothic and utterly preposterous. And clearly no more than an early working draft. The "Emma" of the title does not even appear.

Unfinished novels (like Dickens' Our Mutual Friend or Jane Austen's Sanditon) inevitably entice other imaginations to complete them. Meanwhile, even finished Brontë novels have a history of attracting a range of literary meddling, from prequels (like Jean Rhys' Wide Sargasso Sea), to sequels and parallel texts (like D M Thomas' saucy novella Charlotte). It is hardly surprising, then, that Clare Boylan is not the first to attempt to finish Emma. Frances Hodgson Burnett appears to have been inspired by the two chapters in the Cornhill when she wrote A Little Princess. An Emma by Charlotte Brontë and 'Another Lady' (widely rumoured to have been Elizabeth Goudge) was published anonymously in 1980. I myself did a fun dramatisation of a young fan cheekily completing Emma (The Day I Finished Off Charlotte Brontë, starring Patricia Hodge) on Radio 4 last year.

Emma Brown is a highly enjoyable interpretation of Brontë's intentions, deftly turning an enigmatic sketch into a rich, humorous oil painting. Whereas Brontë would have felt free to go back and adapt her opening chapters as the novel evolved, Boylan respectfully retains the text in aspic and vivaciously explores their every peculiar hint and far-fetched nuance.

This makes for some ingenious storytelling. In the belief that Brontë would have incorporated the social awareness developed during her visits to her publisher in London, Boylan draws material from Mayhew's London Underworld. The graphic descriptions of child prostitution and street urchins who scrape a living by following dogs to sell their droppings to the tanning industry sit hilariously alongside more traditional Brontë settings of repressively respectable Yorkshire drawing rooms "where the limbs of furniture are clothed for decency, and ladies preserved (like pickles) from the harsh realities of the world". Boylan seamlessly weaves other Brontë material into her narrative, so that the whole is a delightful, clever pastiche, confident enough to make fun of itself - as when the po-faced narrator Mrs Chalfont, the very parody of a Brontë narrator, describes the moment she realised that the grocer she had married for his money was penniless: "He laughed again. I could not be comfortable with the sound for it lacked the solace of shared humour. 'I got you on tick, my beauty,' said he."

Charlotte Cory's 'Imperial Quadrille' will appear next year from Harper Collins