Joanna Briscoe: 'I knew I was entering sensitive territory...'

Joanna Briscoe describes her brand of 'erotic suspense' to Catherine Taylor

While Joanna Briscoe's last novel, 2005's Sleep With Me, dealt with a terrifying obsession, her new book, You, has as its provenance a very different preoccupation.

The recurring memory of a remote house on Dartmoor where Briscoe spent a significant part of the 1970s growing up was "haunting me," she explains. "I thought that if I wanted to write about it so much, it had to be with someone returning."

That someone is Cecelia Bannan, a children's writer in her forties who has decamped with her partner and three daughters from London to her childhood home in Devon. The move has been made because Cecelia's widowed mother, Dora, is ill with cancer. But Cecelia is also pursuing a phantom from her past: a baby given up for illegal adoption, in murky circumstances about which the guilt-ridden Dora is deliberately withholding information.

Briscoe has written previously, corrosively, of a competitive mother-daughter relationship in 1994's Mothers and Other Lovers, but in You this interaction is overwhelmingly, she says, not one of rivalry. "Here I see it as real love and real closeness," she says. "I meant it to be a good maternal relationship because I don't often write those." But the characters' closeness is jeopardised by Dora's role in the summary removal of Cecelia's baby. In silkily transgressive prose, Briscoe rolls back the years to reveal the parallel illicit relationships that both mother and daughter were having at the time, and which had a catastrophic effect.

Dora, a harassed music teacher, and her husband Patrick, have embraced a vaguely alternative lifestyle. When Cecelia is enrolled in Haye House, the "progressive" school where Dora teaches, she is horrified at the lack of discipline. But at 17, her fecund imagination is fed by the robust beauty and resonant tones of her English teacher, James Dahl, who arrives like a rare species in the lax environment of Haye House. The two are drawn together; accidental meetings are stoked into a full-blown affair. Simultaneously, Dora has been seduced by James's wife Elisabeth. Their physical encounters are no less urgent than Cecelia's equally intense derailment.

Briscoe agrees that there is a strong element of erotic suspense in her fiction, which she says "often deals with longing, with desire and the tension created by that, more than the actual sex". Writing about Cecelia's involvement with a much older man "could be construed as shocking", she admits. "The girl is not underage, but in exploring that imbalance of power, I was entering sensitive territory, and found some of that very difficult." It's testament to Briscoe's considerable skill as a writer that this relationship between importunate schoolgirl and repressed teacher is portrayed with immense sympathy, if not without cliché.

Sitting in Briscoe's comfortable, book-lined living room in the north London house she shares with the novelist Charlotte Mendelson and their two children, we are a world away from the elemental landscape and raw emotion surging through You. Yet Briscoe's surroundings, the comparatively "wild countryside" of Hampstead Heath, got her "thinking about the house in Devon again". The result is in stark contrast to the stifling urbanity of Sleep With Me, which is set almost exclusively in Bloomsbury – although there is a similar sense of encroaching outsiders. Elisabeth is a sphinx of a woman who holds Dora in a lifelong thrall, while James's encounters with the adult Cecelia threaten to undermine her present-day stability.

The creator of these entanglements ("It's like playing God," she says) is engaging, thoughtful and lively. When asked about living with a fellow writer (would it not, for example, be easier to be with a chemical engineer?), Briscoe laughs somewhat warily. "Much easier, but much less interesting ...." The two have separate studies and dovetailing careers – Mendelson is also a part-time publisher; Briscoe a literary critic. They are each other's first readers, but only when work has reached a certain point, and perhaps fortuitously, they have never yet had a book out in the same year.

Briscoe wanted to be a writer from the age of 15. Like Cecelia in You, she devoured literature and wrote full-length children's novels as a teenager – which, to her then devastation, were rejected by publishers. The many children's book first editions in her house today are evidence of an enduring interest. Briscoe describes her younger self as "hid-eously, painfully, shy and aching with self-loathing and lack of confidence generally. But I had this certainty that I would be a writer – rather than confidence that I could actually write."

She read English at University College London, although "I'd worked so hard at school, I felt almost burnt out at university." Her preference is for "solitary, slow reading", which has its origin in those crucial early years, "the most intense reading experiences of my life". Briscoe candidly admits that she finds the process of novel-writing excruciatingly hard (her first book was 10 years in the making). Yet there is a slow burning, tantalising feel to her work which pays off. Re-reading is significant – she cites Patrick McGrath and Hardy as favourites.

There is certainly a Hardyesque element to You. Briscoe has a wonderful ability to realise landscape and nature. The book teems with wildlife, and emotions headily attuned with the seasons. Imbuing everything is Cecelia's lost baby ... "the child had stayed here all along, here where the wind blew and the ponies' manes made limp flags."

Briscoe is returning to a London setting for her next book, which, she says wryly, will focus on mothers and sons rather than mothers and daughters. Doubtless it will retain You's imperative message, evocative of all her fiction: "What is it you plan to do/ With your one wild and precious life?"

You, By Joanna Briscoe (Bloomsbury, £11.99)

"She played the scene back, watched herself with him from above. She was a girl in a dress with hair falling night-dark over white skin; a girl embraced and kissed for long seconds by an adult man older and tall and heavy in a coat. She saw herself pressed beneath her teacher, her mouth being kissed, and elation soared through her, followed by disbelief."