IF a week is a long time in politics, in literature, a lot can happen in a day.

Saturday, February 15, 2003 is the setting for Ian McEwan's new novel, the day of the anti-Iraq war march in London, the largest gathering of people for a demonstration.

McEwan is a master of the dark and, here, the anxiety of the approaching war and the broader uncertainties of the new world order post September 11 are the black holes in which he shines his torch.

On this foundation of angst he constructs a world of accomplishment and contentment in the shape of Henry Perowne and family.

Perowne is the man who has it all: great job (neurosurgeon), devoted family (loving wife Rosalind, top lawyer; daughter Daisy, published poet and son Theo, promising blues guitarist), dream house in the heart of London, good friends and a flash car.

And yet, the new political climate leaves Perowne on edge. He acknowledges his good fortune, and enjoys it, yet is aware of what little it would take for it to evaporate. A hijacked plane. A bomb on a railway line. Or perhaps a suicide bomber.

On this day, Perowne is planning a reunion dinner for the family, but first he has to fit in a squash game, a trip to the fish market and a visit with his ailing mother.

The day starts badly when Perowne spots a plane coming down on the outskirts of the city and fears a terrorist attack. Later, a road rage incident brings him into contact with Baxter, a London tough nut, prone to bouts of extreme violence.

Terror, real and imagined, at home and abroad, sit together and spread like an unmerciful cancer through Perowne as the novel reaches its climax.

McEwan has taken a bold turn in writing such a contemporary novel, but his insights into the grave new world in which we now live are as meaningful as they are menacing.

Underpinning it all is a brilliant portrait of Perowne, of his hopes, his loves, his family, his work and his fears, written with the gift of detail of the finest miniaturist and with the care and craft of the best surgeon.

Saturday is the dissection of one man's life as well as the life of man at the turn of the 21st century.

Updated: 09:06 Saturday, February 12, 2005