Books: Blowing in tyhe wind

Ian McEwan's latest novel covers some of the territory familiar to his readers: obsession and its consequences, violent events, moral dilemmas. But `Enduring Love' also shows a new tenderness

It begins like a movie, or a dream. Joe Rose has taken his wife Clarissa for a picnic in a Chilterns field. It's a lovers' reunion: she has been away for some weeks, doing research into some lost love letters of John Keats; he has lovingly bought an expensive birthday present and a nouveau Italian feast of mozzarella, focaccia and olives, and a 1987 Daumas Gassac. Meeting her at the airport, waiting at the arrivals gate in a crowd of eager others, Joe, a scientist, decides that Darwin was right about the universality of expressions of emotion in human beings: "I saw the same joy, the same uncontrollable smile, in the faces of a Nigerian earth mother, a thin-lipped Scottish granny and a pale, correct Japanese businessman as they wheeled their trolleys in and recognised a figure in the expectant crowd."

There is a great deal of love around in Enduring Love. From its first pages, McEwan stamps on to the narrative his double trademark: he creates an opening that is unforgettable (like that of A Child in Time), he leaves us in no doubt about his main theme, and at the same time wraps us up in so much movement that we have very little time to think about it.

For it's back to the action shots, to the Chilterns field and the Daumas Gassac. The camera zooms in on the neck of the bottle, cool in its black foil; the soundtrack picks up random shouts, a child's cry, disjointed sounds carried on the wind. Change of camera-angle: from the eye of a buzzard wheeling overhead we see several tiny figures, men running from all corners of the field towards a hot-air balloon that is blowing and bumping out of control, a child frozen with terror inside the basket.

It all happens quickly, of course, and rather preposterously, as things do in life: the five converging men grab the dangling ropes, everything seems safe, then a small movement is bungled and a strong gust lifts the basket, suddenly the men are hanging above the ground. "What is certain is that if we had not broken ranks, our collective weight would have brought the balloon to earth a quarter of the way down the slope a few seconds later as the gust subsided." But "letting go was in our nature, too" and so "our crew enacted morality's ancient, irresolvable dilemma: us, or me".

One man is carried off by the balloon, falls from a height and is killed. There is a brilliant and haunting description of his collapsed body sitting uncannily upright in the middle of a field, the bones internally shattered so that it was nothing but a loose and formless bag, "a head on a thickened stick". But McEwan does the same again - leaves us no time to absorb this shock, or to linger over the moral dilemmas he has outlined for us (whose fault was it? could they have prevented it? is self-preservation a stronger human urge than co-operation?). For, at the moment of this drama and this death, something else has happened, the thing that is to shape the rest of the novel and to play counterpoint to the theme he has already begun to weave.

What has happened is that Jed Parry, one of the other men brought there by chance, trying to save the balloon, has taken one look at Joe Rose and fallen madly and obsessively in love with him. Parry is a young and skinny religious fanatic with high cheekbones, bright new trainers, a ponytail and (we later discover) a private income - all useful attributes, it turns out, for a successful stalker. And indeed he turns out to be the most determined and resourceful of stalkers, always there (even in the London Library), always watching and writing and calling, constantly and unabashedly invoking God and the higher purpose. He also evolves a nightmarish twist to the basic business of obsession: Parry is convinced that it was Joe who fell in love with him, rather than the other way round. One letter ends "I can't help feeling that every time I leave you I'm letting you down. I'll never forget the time at the bottom of the hill, the way you turned away from me, rejected, stunned by my refusal to recognise in that first instance our love. I'll never stop saying I'm sorry. Joe, will you ever forgive me?"

In the face of such craziness, what would you do? Laugh? Or somehow watch helplessly, as Joe does, while Parry's obsession slowly corrodes his confidence and his life, and inserts tiny levers into "the fine crack of estrangement" that opens between him and Clarissa? McEwan's task here is a difficult one. He has created a powerfully real picture of a loving, even passionate marriage; a rounded and compelling character in Clarissa; in Joe a coolly intellectual (if intellectually disappointed) scientist who digresses on the topic of theories, like that of Einstein, which are accepted for reasons of their elegance. Now his authorial job is to make us believe that a nutcase like Parry, however insinuating, could destabilise this pair to the point where they separate. A theory surely rejected for reasons of inelegance.

There are sub-plots - the widow of the fallen man has to find out why he was in the field at all; Joe tries to revive his academic career. There is a moment of mistaken, murderous violence as the denouement comes: McEwan has a weakness for the rough stuff, and is very good at it, as he showed in The Innocent. There is also an overlay of science - now so fashionable in the literary novel (cf Jeanette Winterson and others) - which is put to use pointing up moral dilemmas, or thoughts on the human condition, and which we could probably manage without.

If the science is the novel's least convincing element then its core, the devastating effect of obsession on normality, the power of pathological love against the merely loving, is never in doubt. McEwan does a superb job of making us believe what seems so unlikely, and that is the book's great power. At the end come several appendices, mainly on de Clerambault's syndrome (Parry's problem, since you ask). This is a mildly disappointing way to finish such a fine book (when does postmodern begin to look quaint?) and if I had been reading the novel purely for fun I would probably have skipped them. If I had, though, I would never have found out what happened to Clarissa and Joe, and their version of enduring love.

! `Enduring Love' is published by Jonathan Cape on 4 September at pounds 15.99