Hearts and Minds, By Amanda Craig

The theme of Hearts and Minds - shadowy, unwanted migrants in London - began to excite literary London five years ago, leading to a cluster of novels by accomplished old and new writers. Film-makers had got there first: Stephen Frears made his gritty Dirty Pretty Things, followed by Anthony Minghella's Breaking and Entering and Ghosts by Nick Broomfield.

Until recently, creators of fiction ignored the human detritus swilling around global cities, London most of all. The "feral" subterranean creatures were not worthy of their attention. Now they are, it seems. Rose Tremain's The Road Home won the Orange Prize; Marina Lewycka's A Short History of Tractors in Ukrainian sold millions; Maggie Gee's last two novels explore the relationship between a messed-up white female lecturer and Ugandan servants. Monica Ali's new novel, In the Kitchen, is set in a hotel which employs floating migrants (a setting brilliantly exploited in the Frears film) and Chris Cleave's The Other Hand pulls together separate lives and trajectories - a frisky magazine editor and a 16-year-old Nigerian asylum-seeker, for starters.

Although the marketplace is crowded, Craig's tome will still hold its own because she eschews laboured profundity. Her style is immediate and precise, and convincingly dramatic. She skilfully mixes skilled reportage (once a journalist, always a journalist) with a filmic sensibility. Her heroine, Polly Noble, appeared first in Love in Idleness, an upper-middle-class romp in Tuscany. Polly had a rich American husband and two children. That is all gone. Now a divorced single mum, she is an immigration lawyer with heart.

There is something about Polly that makes her appear insincere and irritatingly naive. But that's why she is credible. How many such people do I know, who froth with pity for incomers and "celebrate" our metropolitan diversity yet readily exploit or mistrust "illegals"? Even when transformed by climactic events, Polly can never really never understand what it is to be stateless and lost in transition.

Iryna, her Russian au pair, vanishes. All that matters to the caring solicitor is her domestic chaos. It is too late when she faces up to the instinctive selfishness of her class: "The empty room upstairs haunts Polly. She goes up to it at night. Its forlorn, tatty walls are a reproach. Perhaps it was never as nice as she thought, or perhaps it is the guilt about all that she has failed to do". Iryna's death means there can be no forgiveness. Her body is "just one more discarded thing which will be counted as lost, if she is counted at all".

Other characters appear and reappear as if on a merry-go-round, lives linked, then parted, brought close only to move on too fast; too many really, so you barely care about some. Dickens could do multiple stories and people, in part because many were caricatures. The realism of modern writing makes different demands. Less is more.

Job the Zimabwean cabbie, sensitive, educated and immeasurably sad, grips your heart. So too Kitty, the desolate American, and Ukrainian Anna the teenage sex slave (although her pimps are off-the-shelf stereotypes). Less convincing and too obvious are the philandering magazine editor, his cynical wife and long-lost son.

I could have done without the social commentary on bad schools and bad NHS and bad police and bad children and bad Muslims and bad metropolitan karma. London works and redeems. Somehow even those forced into prostitution can make a new start here and the dispossessed find love in our cold climate. Thankfully, that optimism comes though as the compelling tale unfolds. You can't put this novel down, even if babies are yelling and the pots are boiling over. It is not Craig at her best nor most ground-breaking, but Hearts and Minds is, nevertheless a terrific read.

Yasmin Alibhai Brown's 'The Settler's Cookbook' is published by Portobello