The Rain Before It Falls, by Jonathan Coe

Should truth be paramount? That is the question that dangles at the end of Jonathan Coe's beautifully titled new novel The Rain Before It Falls, and it is one that the author neatly side-steps.

The 73-year-old Rosamond, knowing she is nearing death, spends her final hours relating a family history into a tape in the hope that the all-important "truth" will reach the mysterious Imogen, a character we never meet. We learn that Imogen is blind and was adopted out of the family, aged three. Lucky for her. Such a poisonous family this is, so nasty the truth, one can't help but feel she had a fortunate escape – particularly as she appears to have grown into a happy, intelligent, fulfilled young woman in the bosom of her adoptive family.

Could this whole project be Rosamond's ego trip? After all, Imogen is a relatively peripheral character, her function arguably that of an excuse for Rosamond to tell her life story.

For a prelude, we are introduced to the family of Gill, Rosamond's niece. Just as Imogen is an ostensible reason for the tapes, so Gill, as executor of her aunt's will, is a device to gain us access. This circuitous approach is not, in itself, a problem, but what compounds the sense of artifice is the structure of the tapes. Rosamond has chosen to describe a series of 20 photographs, 20 stories slowly revealing to Imogen "the forces that made you", and ultimately a horrible truth.

This is a very neat, and suspiciously writerly structure. Of course, the reader should accept a certain amount of poetic licence. But when Rosamond, speaking into the hand-held microphone of a primitive recorder, launches into hours of effortless and polished prose, complete with dialogue, parentheses and well-judged digression, the hurdle of disbelief becomes even more difficult to clear. So, when one of Gill's spellbound daughters, who has been listening to the tapes, asks simply, "Did you know about all this, Mum?", one is amazed she does not say instead: "Gosh Mum, whoever would have guessed old Aunt Ros had such an accomplished literary style?"

All this is by way of saying that Jonathan Coe is a consummate and skilful writer. The Rain Before It Falls is an unsettling account of three generations of appalling mother-on-daughter abuse – mental, emotional and physical. From Rosamond's superficial Aunt Ivy, who offers her a home as a wartime evacuee , through her emotionally starved cousin and "blood-sister" Beatrix, to Beatrix's daughter Thea, a selfish child of the Sixties, the cycle is laid bare. Coe is astute at nailing the chance happenings that influence a life, and the enduring nature of even the most destructive of relationships is portrayed in all its complexity.

These three women come in for harsh judgement from the apparently omniscient woman with her microphone. Should truth be paramount? The question is never answered. By the end, I couldn't help feeling that Rosamond, self-appointed bringer of a questionable enlightenment, is in many ways as flawed as the worst of them.

Carol Birch's new novel, 'Scapegallows', will be published by Virago in November

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