^“‘You pearl,’ I said. So white she was.” With these words, Sarah Waters confirmed the arrival of a world-class writer capable of turning conventional literary erotics upside-down and inside-out. The dialogue is uttered in a scene of lesbian lovemaking that has been cited by both male and female, gay and heterosexual commentators as one of the sexiest encounters in literature.

Waters’ first two novels, Tipping the Velvet and Affinity, had signalled a powerful new voice in lesbian fiction, but Fingersmith took it to a new level, its kaleidoscopic prose and structure creating a dizzying variety of desires and perspectives. Shortlisted for the Booker prize, it was one of David Bowie’s 100 must-read novels and has had a lusty afterlife in theatre and TV.

Published in 2002, Fingersmith is a story of deception involving a pickpocket, a conman, a pornographer and an heiress. Now it has been reimagined in film by Korean director Park Chan-wook, who has defied differences in culture, gender and media to create a complementary classic of erotic cinema.

The Handmaiden transports the story from Victorian England to Korea in the 1930s, when the peninsula was occupied by Japan. In the novel, the pickpocket Sue is lured away from a bustling thieves’ kitchen in London to the countryside with the promise of a share in a soon-to-be-stolen fortune; in the film, seamstress Sook-hee is hustled off into a rainstorm on an undeclared mission at the house of a rich Japanese recluse, leaving a wailing chorus of women and babies huddled beneath the eaves of their roadside shack.

Fans of the novel might well wonder how Waters’ richly verbal story of lesbian sexuality – a gasp of release from the sensuously evoked corsetry of Victorian female propriety – could survive this transformation, and not least because the director is a man, with a reputation for making macho films of extravagant violence.

Waters herself concedes that “it seemed a slightly mind-boggling idea”. She was involved in selling the film rights along with the company that had made a well-received three-part TV adaptation, and steeled herself to find out what she would be letting herself in for by watching Park’s 2003 revenge tragedy Oldboy. “I loved it because it was so gloriously excessive. Melodrama isn’t the word really. It’s more Greek myth.” Fingersmith, she points out, is excessive too, with its roots in “those Victorian novels about murder and madness and mayhem”.

In person, Waters seems about as far from madness and mayhem as it is possible to be. At 50, with six novels to her name, she lives the quiet life of a professional novelist in south London with her partner of many years, Lucy Vaughan. Where Fingersmith is full of bodices and petticoats, the softest leather and the most lustrous silks, its author is most likely to be found in jeans.

When I pull an old paperback of Fingersmith out of my bag she looks surprised and says, “It’s very big, isn’t it?” It takes a few seconds for the significance of this to sink in “I’ve never reread it,” she admits, adding that the only one of her six novels that she has reread is Tipping the Velvet “and all I wanted to do was tidy it up”.

“One of the nice things about adaptations is it gives you a chance to revisit the story and characters,” she says. Four of her novels have been adapted for television and in the three Victorian romps – including Fingersmith – she made cameo appearances. The fourth adaptation, The Night Watch, a chronologically reversed story set in the second world war, reflected the shift in her writing to more nuanced and sombre worlds. Her fifth and sixth novels have both been optioned for film, with her most recent, The Paying Guests, being adapted by Emma Donoghue, author (and adapter) of Room.

But it is The Handmaiden that marks her first excursion on to the big screen, and she regards the ingenuity of the plotting with an almost parental delight, as the work of a younger, more playful self that the film has not so much mimicked as amplified, with its own ingenious twists and turns. “I don’t know if I could do that today. My brain was young and juicy in those days and I could do those kind of things.”

Waters began writing fiction while waiting to hear about a grant that would have enabled her to continue on the route to becoming a career academic. She had followed an MA in gay and lesbian historical fiction with a PhD on the idea of history in lesbian and gay writing. “Writing Fingersmith I was at my most immersed in the 19th century. I was just in love with the Victorians,” she says. “It does get a bit breathless but that was very much a homage to the novels of sensation: to Wilkie Collins or Mary Elizabeth Braddon.”

Her first novelistic flush also coincided with a high point for lesbian feminism in the UK, which she enthusiastically embraced as a Welsh Catholic schoolgirl who had been to university in Lancaster and then washed up in Stoke Newington, the historical centre of London’s dissenting culture. “The bad haircut, the awful clothes, and everything politicised. It was so exciting,” she has said.

Fingersmith is in some senses very much of its time – “To me it seems like quite an old-fashioned lesbian story. I think of queer as a 90s thing.” But her Victorian novels have found a new resonance decades later, with their themes of love, deception and the capacity of women, particularly those disadvantaged by class, to overturn the social order by swapping identities. “Unlike Tipping, Fingersmith doesn’t have gender impersonation, but it has other sorts of impersonation.”

She looks back fondly on its evolution. “It was a fun book to write: it had a lot of verve. It was me finding my feet as a novelist. Tipping had lots of energy but it was very much a first novel, a bit overwritten and untidy. Affinity was me getting my skill. I thought with Fingersmith that it was me starting to learn my craft and it’s the novel of all of mine that gets excitement back from readers and especially young women readers.”

In The Handmaiden, pickpocket Sue and the lonely heiress Maud become Korean thief Sook-hee and Japanese Hideko, pawns in a power game that is at once sexual, mercenary and colonial, reflecting a period of Japanese occupation that still rankles in south Korea today. The dialogue is in both languages, with colour-coded subtitles to signal which is being spoken at any one time.

“The first thing that struck me was how faithful it manages to be to Fingersmith even though it’s in Korean and Japanese and set in a different period,” says Waters. “I was very interested in the texture of Victorian life, and the power dynamics were played out in a material way, and I think he’s brought a similar interest in artefacts and fabrics. It’s such a crowdedly lush film, with all those shoes and gloves and corsets.”

It is atmospherically set in a mansion which is part western gothic, part Japanese, with rooms divided by sliding paper doors through which the unscrupulous can snoop on the unwary. Like the castles of classic gothic literature, both novel and film create spaces in which the normal order can be subverted. “Those buildings with rooms after rooms after rooms are psychic structures,” Waters observes. “They echo social structures: public or semi-public spaces, then private, then secret spaces.”

It’s in the secret spaces that the film becomes most powerful and, on occasion, troubling. It raises questions about power, pornography and point of view that are different from those raised by the novel. “[Park] does a lot more with the pornography because he turns it into a spectacle. For me it was all about words,” says Waters, a self-confessed “theatre-nut” with a connoisseur’s appreciation of the timing and rhythm of the film’s extravagant set pieces.

The novel confronts porn’s erasure of the realities of the female body, such as pubic hair, with the suggestion that sex between women involves pleasure in a different sort of body. While luxuriating in 16-inch waists cinched tight by corsets and hands softened by kid gloves, Waters is also alert to the white-rimmed blotches of sweat-stained armpits and feet battered by silk shoes unfit for walking.

In the film, Hideko is forced to recite stories of women with “Jade-gates ... as white as snow, as smooth as jade and as tight as drums”, but there is little in the representation of the two beautiful young women making love that insists on a less idealised representation of physical intimacy between women.

“They are like mirrors of each other which I’ve found rather troubling in the past because it blacks out the difference, but when I spoke to Park he said he was bringing the Japanese mistress and the Korean sewing girl together on an equal level,” explains Waters. “The novel is about class rather than gender: people passing themselves off as something they’re not. The film is more about colonialism: that very fraught relationship between Korea and Japan.”

Prurience is held at bay by two recurrent motifs. The uncle’s porn literature is recited publicly to audiences of men who squirm comically with lust in their seats before a performer – Hideko – who is painted and coiffed into an expressionless mask. In what Waters describes as “a very fine scene”, she mounts an airborne marionette in a stately simulation of sex.

In the film, as in the book, the key to a sexuality that is exclusive to women is the exchange of body fluids. “Maud having sex for the first time is a very moist experience compared with the dry experience of a book,” says Waters. The lacquered artifice of Hideko’s performances also contrasts with the juiciness of the women’s love-making, which begins with an exchange of lollipop-flavoured saliva and ends with the oral lubrication of Japanese sex toys.

Nowhere is this correspondence more powerful than in the pivotal “pearl” scene, that famous first coupling of mistress and maid. In the novel, servant Sue inducts Maud in the art of sex, ostensibly to prepare her for her wedding night. As readers, we know Maud is slave to her book collector uncle, but we don’t yet know the nature of his books. As the illiterate child of a house of ill-repute, Sue is well educated in the ways of the world, so it seems like a comment on different sorts of knowingness.

The film reveals the nature of the books early on as part of the back story of Hideko, who has been taught to read using pornographic texts. Her precocious reading, as a copyist and performer of these graphically illustrated works, creates a different sort of irony, giving her a sexual expertise which we understand, even as it mystifies her instructor. “So innocent … you must be a natural,” Sook-hee comically gasps.

Part of the scene’s power comes from the fact that it is played twice, with the result that Sue’s climactic words in the novel – “You pearl, you pearl, you pearl” – become doubly erotic. The film repeats this trick, showing Sook-hee’s face glistening as she emerges, full of wonder, from between her lover’s legs. “Women’s secret parts,” she pants, are “soft, wet and warm … and spell-bindingly beautiful.”

When I say that I found the lingering intimacy uncomfortable to watch, because it sails so close to traditional girl-on-girl porn, Waters counters that younger women and young queer people appear to be welcoming it. “Fingersmith was about finding space for women to be with each other away from prying eyes,” she says. “Though ironically the film is a story told by a man, it’s still very faithful to the idea that the women are appropriating a very male pornographic tradition to find their own way of exploring their desires.”

• The Handmaiden is released next week.