NOTES ON A SCANDAL. By Zoe Heller. 243pp. Viking. Pounds 14.99. - 0 670 91406 1

Bathsheba Hart -Bash to her husband, Sheba to her friends -is at the centre of Zoe Heller's second novel. Nearing middle age, she is as alluring as any of Thomas Hardy's soft-eyed heroines: one of those kind, ingenuous, perennially pretty women who attract people of all ages and both sexes. At twenty she married a much older lecturer because he asked. "I wasn't even pregnant", she laughingly reflects. Soon there was a daughter, a son with Down's syndrome and a big house in North London to care for.

Notes on a Scandal begins when Sheba's maternal duties are receding and she takes a job teaching pottery in a local comprehensive school. Arriving on a bicycle in a blur of dishevelled hair and semi-transparent clothing, Sheba immediately experiences "class control issues". There are cries of "I fancy you, Miss!" and "Show us your tits!" from Year Nine, a clay fight in Year Eight, and physical violence during Homework Club. In the mayhem, fifteen-year-old Steven Connolly starts to pursue Sheba ardently. After an awkward, quintessentially Lawrentian conversation in the art room at dusk, a first kiss entangled with her bicycle and a chilly stroll on Hampstead Heath, they are deep in an illicit affair.

Her senior colleague and confidante, Barbara Covett, narrates Sheba's cliched story. Barbara is a lonely obsessive, relishing the opportunity to live vicariously. "I am presumptuous enough to believe that I am the person best qualified to write this small history." As Sheba awaits trial for indecently assaulting a minor, Barbara makes notes on events leading to the two women living together, shunned by society and persecuted by the press.

The contrast between Sheba and Barbara is that between sentimentality and cynicism. It can be very droll. Regarding Sheba's frequent rhapsodies on her lover's hair -limp with cleanness and the vanity of adolescence -Barbara remarks: "I've never cared for Connolly's hair, myself. It's always struck me as slightly sinister -like that spun-fibreglass snow that they used to sell as Christmas tree decoration". While Sheba insists on the extraordinarily romantic nature of her affair, Barbara believes all courtship is cynical: a matter of tricking out one's stall to attract a particular customer. "The sort of young person who becomes involved in this kind of imbroglio is usually pretty wily about sexual matters." Taken to extremes, both sentimentality and cynicism undermine morality. For their different reasons, Sheba and Barbara ignore entirely the moral implications of sex with a minor.

Connolly's raging mother, Sheba's traumatized family, the incredulous Blair like headmaster, the shrill tabloid press, all help themselves to morals as substantial as stones.

Heller's first novel, Everything You Know (1999), achieved poignancy by contrasting the perspectives of a selfishly dissolute father and his vulnerable suicidal daughter. Her new novel refines this simple technique. Barbara's selfishness and Sheba's vulnerability are psychologically compelling without relying on cross- gender or generational differences. Instead, class distinctions are important in defining the two women. Barbara is fascinated by Sheba's busy bourgeois London life: the boisterous children's parties; the mismatched, oversized, effortlessly elegant furniture; the drawled greeting, "Oh, Helleh". This predatory spinster, lost in "the white wastelands of my appointmentless weeks", means to be alone with Sheba -the scandal is her best opportunity.

Heller is a successful journalist and her novel exudes the disabused good sense she imparts to a fictional "chap from the Evening Standard": "What red-blooded fifteen-year-old wouldn't welcome a roll in the hay with Sheba Hart?". She is more though than a journalist made good. Notes on a Scandal is as accomplished as any of the writing recently showcased in Granta 81. Ultimately, it turns on a careful exploration of emotional dependency. What Barbara unreasonably wants from Sheba is a simulacrum of marriage: "the ebb and flow in the pleasure a couple take in one another". There is something deeply repugnant about the cosseting she lavishes on her distraught friend while patiently awaiting "my time for some attention". Without condoning illicit sex, Zoe Heller offers an amusing, intelligent reminder that worse things happen in the human heart.

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