Lesley Grant-Adamson does ordinariness very well. She describes the thoughts and actions of ordinary folk in ordinary language. But since she writes thrillers, she also concerns herself with the extraordinary: with extreme emotions, unthinkable memories, unusual violence. And she writes about these in the same way. This is her strength.

Lipstick and Lies is principally narrated by Anna, a middle-aged woman in whose family a "sensational" murder took place when she was eight. Forty-five years later a criminal justice investigation takes a peripheral interest in the crime (which is not central to its case against a bent forensic scientist). The enquiries unsettle Anna and force her to confront buried truths.

Anna shares her journey of rediscovery with the other surviving family member, her cousin June, a dull old spinster with a bad leg and a persistent grumble about delivery men. Anna has a PR job, a taste for expensive classic clothes and, as it turns out, a sad marital history to add to her lamentable childhood. But her life now is hardly less staid and uneventful than her cousin's. Between them, the two inhabit a world of banal domesticity: the highlights of Anna's visits to June are when she takes the fat dog for a walk in the park.

Grant-Adamson conveys the twinsetty twilight years of these two ladies with a plodding credibility, and a good deal of utterly inconsequential detail, some of which gets pointlessly repeated (where was the editor?). But at the same time she hints at something horrid. Bit by bit, Anna recalls the circumstances of a black deed in a youth full of stereotypes: her father who was not quite right after the war, her fast mother who was no better than she ought to be, and her mother's spivvy fancy man. Grant- Adamson is scrupulous about Fifties detail, but - like the Humber cars, grosgrain dresses and seamed stockings - her Fifties characters seem to come out of a box marked "stock".

And yet. When it comes to the moments of real drama, Grant-Adamson's lack of pizzazz, her mundanity and understatement, are arresting. The quiet ellipses with which she describes cruelty, grief, fear, violence and tragedy invest them with power: the power of what is unsaid. In these moments her language has a redeeming grace. And she has flashes of wit. Anna sees her dead mother's face everywhere: "Since she died she has been on television, taken part in an Australian soap opera, won a lottery ticket ... and once, spectacularly, she figured in the tearing down of the Berlin Wall."

The principal revelations of the murder are not a surprise, but the very fact that the ending is half-predictable is an incentive to keep reading. This thriller is not a pacy page-turne, but it does have a soap- opera-ish fascination; and you do keep turning to be sure you've guessed right.