The Flood by Maggie Gee

Swept away by a deluge of decadence

Like Margaret Atwood, Maggie Gee has always shown a readiness to tackle ideas on a grand as well as a domestic scale. In The Ice People, Gee evoked a world in the throes of climactic catastrophe. She followed it in 2002 with the Orange Prize-shortlisted The White Family, a sharply-observed and humane portrait of an ordinary family eaten alive by its own racism. After two such ambitious and successful novels, it isn't hard to understand why Gee was tempted to experiment by taking the apocalyptic scenery of The Ice People and the domestic realism of The White Family, and combining their DNA to create a new life-form with its own agenda.

The result is The Flood, a novel in which the remaining members of the White family - altered by death, imprisonment and new birth - re-appear in a London half-submerged by chronic flooding and nudging towards the brink of a seemingly localised Armageddon. Gee pulls off the splicing feat - deftly, but only just - by making sure that the family's new backdrop bears enough uncanny parallels to the London they inhabited before. So the characters don't notice they have slipped through the looking-glass into a horribly plausible dystopia.

The reconstituted London is "a city of pain and music and crisp packets" (so far, so familiar), capital of a sodden, fox-infested archipelago at war with the Muslim nation of Loya (a thinly veiled Iraq), in thrall to Hesperica (guess where) and governed by the ever-smiling people-pleaser Mr Bliss (no prizes there). What emerges is a crowded ensemble piece, featuring not only the family, but a self-deluding novelist, a TV astronomer, his spoiled mother, and inhabitants of The Towers, the partially submerged quarter that seems to house the city's underclass.

Gee's ability to ask big "what if?" questions while never losing sight of the humdrum details of life - sex, envy, children or household finance - gives her un-brave new world credibility. For the first half of the novel, the reader enjoys the harmony between macro and micro, and the emerging connections between the disparate characters and their social worlds. But as more people get caught up in the narrative flow, drifting like flotsam towards a hazy hinterland signposted Doom, the novel's themes become increasingly random and diffuse.

While the waterlogged city celebrates its much-delayed Gala, a new crisis looms in the form of a "cometoid" hurtling towards earth and creating the prospect of a massive tidal wave. As if that were not enough, "flood-sickness" - a deadly plague - becomes rife. The Gala party goes ahead, and a set-piece ensues in which "It" people flirt and bling-bling.

At this point the novel, whose satire has up to now been quite a muted affair, veers into a savage attack on the unfairness of society and the vanity of the upper classes. By the time the end of the world is properly nigh, the Whites have long since washed themselves down the plug-hole of your interest. This is a shame, in a story that opens with such an exciting premise and contains so many well-drawn characters.

But it may also be inevitable. While a tsunami can sweep everyone and everything up in its apocalyptic narrative, perhaps a book just can't - however interesting it may be to try.