Sarah Waters is not the only leading novelist who once undertook an English literature PhD. (Alan Hollinghurst and Ian Rankin are two others whose academic expertise breathes in their fiction.) Waters's doctoral research into Victorian literature has clearly helped her with the materials for her fiction. The minute attention to manners or food or clothing provides the reader of Fingersmith with some of the traditional pleasures of historical fiction. Never have the details of 19th-century female attire been more important in a novel. At certain points the plot turns on the value of a gentlewoman's petticoats, or the importance of her gloves, or the ability of a woman to hide a file in a boot or a document within the layers of a dress.
Yet the clutter of Victorian detail is only the half of it. Waters calls Fingersmith a "pastiche" because it replicates some of the details of Victorian novels. Its most important kinship is with Wilkie Collins's The Woman in White In Collins's novel the virtuous, naive Walter Hartright is drawn into a deadly conspiracy when he becomes drawing master to the beautiful Laura Fairlie, an orphan whose selfish, hypochondriac uncle lives mostly in his library. Fingersmith gives the situation a nasty twist. Now the handsome drawing master is himself the villain - "Gentleman", as his accomplice Sue Trinder calls him - and the uncle's library is a lovingly assembled collection of pornography. Waters's plot involves Sue's incarceration in a private asylum under a false identity. In a bravura section of the novel, her every attempt at explanation is taken by the supercilious doctors and terrifying nurses to be more evidence of her state of delusion. This recollects from Collins's novel the similar incarceration of the heiress Laura Fairlie under the false identity of Anne Catherick. In both novels, the deception is part of a villain's scheme to possess an inheritance.
"Shall we for ever make new books, as apothecaries make new mixtures, by pouring only out of one vessel into another?" This is the plaintive question asked in Laurence Sterne's Tristram Shandy. Except that it is plagiarised from Robert Burton's Anatomy of Melancholy (1621), one of Sterne's favourite books. Burton himself mocked writers who "lard their lean books with the fat of others' works", but we can admire judicious larceny. Usually it is called intertextuality, a term coined by the French critic Julia Kristeva and one of those rare terms of literary theory that has migrated into the mainstream media. Certainly the reader who knows The Woman in White feels encouraged to recognise aspects of its plot, and derives the extra enjoyment of seeing how these are adapted. The narrative twists of Fingersmith are variations on Collins's plot. When we find out that Maud Lilly, the innocent young gentlewoman who is the equivalent of Collins's Laura, is actually a co-conspirator herself, the turn given to our assumptions about virtuous Victorian maidens is all the more satisfying.
We need something more precise than intertextuality for the ways in which Fingersmith displays its attachment to older novels: literariness, perhaps. It is there in many brushes with Victorian fiction. Some are irresistible turns of phrase. When Sue tells us how one of the rooms in their stinking tenement shelters Mr Ibbs's sister, "who often woke with the horrors on her, shrieking", we might remember Magwitch in Great Expectations recalling Miss Havisham's brother Arthur "dying poor and with the horrors on him". But some phrases are more than colour. When Sue thinks of how her only friends are counting on her to be Gentleman's ruthless accomplice, she echoes Pip's self-deception in Dickens's novel. "I had a certain standing. I was the daughter of a murderess. I had expectations." We keep being taken back to Dickens's association of Victorian social ambition with Victorian crime.
Rather than historical fiction simply trying to make the reader believe in a picture of the past, the past is to be conjured through its own fiction. The technique was pioneered by John Fowles's The French Lieutenant's Woman, which brought Victorian mores to life by calling on its readers' knowledge of Victorian novels. Fingersmith gives a signal of this technique on its opening page, when Sue recalls begging at a theatre where Oliver Twist was being staged. With "the sight of Nancy, lying perfectly pale and still at Bill Sykes's feet" she became "gripped by an awful terror". Back in the thieves' den in Borough where she herself lives, she is reassured by her adoptive "mother", Mrs Sucksby, that Nancy was not dead but only "beat a bit about the face". She later "met a nice chap from Wapping, who had set her up in a little shop selling sugar mice and tobacco". The inhabitants of Victorian London talk as if they know Dickens's characters quite personally.
· John Mullan is professor of English at University College London. Join him and Sarah Waters for a discussion of Fingersmith on June 12 at the Newsroom, 60 Farringdon Road, London EC1. Doors open at 6.30pm and entry costs £7. To reserve a ticket call 020 7886 9281 or email firstname.lastname@example.org