And the forward motion is a prompt, it instantly returns him to his list, the proximal and distal causes of his emotional state. A second can be a long time in introspection. Long enough for Henry to make a start on the negative features, certainly enough time for him to think, or sense, without unwrapping the thought into syntax and words, that it is in fact the state of the world that troubles him most, and the marchers are there to remind him of it. The world probably has changed fundamentally and the matter is being clumsily 80 handled, particularly by the Americans. There are people around the planet, well-connected and organised, who would like to kill him and his family and friends to make a point. The scale of death contemplated is no longer at issue; there'll be more deaths on a similar scale, probably in this city. Is he so frightened that he can't face the fact? The a.s.sertions and the questions don't spell themselves out. He experiences them mure as a mental shrug followed by an interrogative pulse. This is the pre-verbal language that linguists call mentalese. Hardly a language, more a matrix of shifting patterns, con solidaling and compressing meaning in fractions of a second, and blending it inseparably with its distinctive emotional hue, which itself is rather like a colour. A sickly yellow. Even with a poet's gift of compression, it could take hundreds of words and many minutes to describe. So that when a flash of red streaks in across his left peripheral vision, like a shape on his retina in a bout of insomnia, it already has the quality of an idea, a new idea, unexpected and dangerous, but entirely his, and not of the world beyond himself.

He's driving with unconscious expertise into the narrow column of s.p.a.ce framed on the right by a kerb-flanked cycle path, and on the left by a line of parked cars. It's from this line that the thought springs, and with it, the snap of a wing mirror cleanly sheared and the whine of sheet-steel surfaces sliding under pressure as two cars pour into a gap wide enough for one. Perowne's instant decision at the moment of impact is to accelerate as he swerves right. There are other sounds - the staccato rattle of the red car on his left side raking a half-dozen stationary vehicles, and the thwack of concrete against rubber, like an amplified single handclap as the Mercedes mounts the cycle-path kerb. His back wheel hits the kerb too. Then he's ahead of the intruder and braking. The slewed cars stop thirty yards apart, engines cut, and for a moment there's silence, and no one gets out.

81 By the standards of contemporary road traffic accidents Henry has done a total of five years in Accident and Emergency - this is a trivial matter. No one can possibly be hurt, and he won't be in the role of doctor at the scene. He's done it twice in the past five years, both for heart attacks, once on a flight to New York, another time in an airless London theatre during a June heatwave, both occasions unsatisfactory and complicated. He's not in shock, he's not weirdly calm or elated or numbed, his vision isn't unusually sharp, he isn't trembling. He listens to the click of hot metal contracting. Whnt he feels i= rising irritation struggling against worldly caution. He doesn't have to look one side of his car is wrecked. He already sees ahead into the weeks, the months of paperwork, insurance claims and counterclaims, phone calls, delays at the garage. Something original and pristine has been stolen from his car, and can never be restored, however good the repair. There's also the impact on the front axle, on the bearings, on those mysterious parts which conjure the essence of prolonged torture - rack and pinion. His car will never be the same again. It's ruinously altered, and so is his Sat.u.r.day. He'll never make his game.

Above all, there swells in him a peculiarly modern emotion - the motorist's rect.i.tude, spot-welding a pa.s.sion for justice to the thrill of hatred, in the service of which various worn phrases tumble through his thoughts, revitalised, cleansed of cliche: just pulled out, no signal, stupid b.a.s.t.a.r.d, didn't even look, what's his mirror for, f.u.c.king b.a.s.t.a.r.d. The only person in the world he hates is sitting in the car behind, and Henry is going to have to talk to him, confront him, exchange insurance details with him - all this when he could be playing squash. He feels he's been left behind. And he seems to see it: receding obliviously down a side street is the other, most likely version of himself, like a vanishing rich uncle, introspective and happy, motoring carefree through his Sat.u.r.day, leaving him alone and wretched, in 82 his new, improbable, inescapable fate. This is real. Telling himself it is so betrays how little he believes it yet. He picks his racket off the car floor and puts it back on top of the journal. His right hand is on the door catch. But he doesn't move yet. He's looking in the mirror. There are reasons to be cautious.

There are, as he expected, three heads in the car behind. He knows he's subject to unexamined a.s.sumptions, and he tries to examine them now. As far as he's aware, lap-dancing is a lawful pursuit. But if he'd seen the three men hurrying, pvrn furtively, from the Wellcome Trust or the British Librarv he might already have stepped from his car. That they were running makes it possible they'll be even more irritated than him by delay. The car is a series five BMW, a vehicle he a.s.sociates for no good reason with criminality, drug-dealing. And there are three men, not one. The shortest is in the front pa.s.senger's seat, and the door on that side is opening as he watches, followed immediately by the driver's, and then the rear offside door. Perowne, who does not intend to be trapped into talking from a sitting position, gets out of his car. The half-minute's pause has given the situation a game-like quality in which calculations have already been made. The three men have their own reasons for holding back and discussing their next move. It's important, Perowne thinks as he goes round to the front of his car, to remember that he's in the right, and that he's angry. He also has to be careful. But these contradictory notions aren't helpful, and he decides he'll be better off feeling his way into the confrontation, rather than troubling himself with ground rules. His impulse then is to ignore the men, walk away from them, round the front of the Mercedes to get a view of the damaged side. But even as he stands, with hands on hips, in a pose of proprietorial outrage, he keeps the men, now advancing as a group, on the edge of vision.

At a glance, there seems to be no damage at all. The wing mirror is intact, there are no dents in the panels; amazingly, 83.I.

the metallic silver paintwork is clean. He leans forward to catch the light at a different angle. With fingers splayed, he runs a hand lightly over the bodywork, as if he really knew what he's about. There is nothing. Not a blemish. In immediate, tactical terms, this seems to leave him at a disadvantage. He has nothing to show for his anger. If there's any damage at all, it is out of sight, between the front wheels.

The men have stopped to look at something in the road. The short fellow in the black suit touches with the tip of his shoe the BMW's shorn-off wing mirror, turning it over the way one might a dead animal. One of the others, a tall young man with the long mournful face of a horse, picks it up, cradling it in both hands. They stare down at it together and then, at a remark from the short man, they turn their faces towards Perowne simultaneously, with abrupt curiosity, like deer disturbed in a forest. For the first time, it occurs to him that he might be in some kind of danger. Officially closed off at both ends, the street is completely deserted. Behind the men, on the Tottenham Court Road, a broken file of protesters is making its way south to join the main body. Perowne glances over his shoulder. There, behind him on Gower Street, the march proper has begun. Thousands packed in a single dense column are making for Piccadilly, their banners angled forwards heroically, as in a revolutionary poster. From their faces, hands and clothes they emanate the rich colour, almost like warmth, peculiar to compacted humanity. For dramatic effect, they're walking in silence to the funereal beat of marching drums.

The three men resume their approach. As before, the short man - five foot five or six perhaps - is out in front. His gait is distinctive, with a little jazzy twist and dip of his trunk, as though he's punting along a gentle stretch of river. The punter from the Spearmint Rhino. Perhaps he's listening to his personal stereo. Some people go nowhere, even into disputes, without a soundtrack. The other two have the manner of subordinates, sidekicks. They're wearing trainers, track84 suits and hooded tops - the currency of the street, so general as to be no style at all. Theo sometimes dresses this way in order, so he says, not to make decisions about how he looks. The horse-faced fellow is still holding the wing mirror in two hands, presumably to make a point. The unrelenting throb of drums is not helpful to the situation, and the fact that so many people are close by, unaware of him, makes Henry feel all the more isolated. It's best to go on looking busy. He drops down closer by the car, noting a squashed c.o.ke can under his front tyre. There is, he sees now, with both relief and irritation, an irregular patch on the rear door where the sheen is diminished, as though rubbed with a fine emery cloth. Surely the contact point, confined to a two-foot patch. How right he was, swerving away before he hit the brake. He feels steadier now, straightening up to face the men as they stop in front of him. Unlike some of his colleagues - the surgical psychopaths - Henry doesn't actually relish personal confrontation. He isn't the machete-wielding type. But clinical experience is, among all else, an abrasive, toughening process, bound to wear away at his sensitivities. Patients, juniors, the recently bereaved, management of course - inevitably in two decades, the moments have come around when he's been required to fight his corner, or explain, or placate in the face of a furious emotional upsurge. There's usually a lot at stake - for colleagues, questions of hierarchy and professional pride or wasted hospital resources, for patients a loss of function, for their relatives, a suddenly dead spouse or child - weightier affairs than a scratched car. Especially when they involve patients, these moments have a purity and innocence about them; everything is stripped down to the essentials of being - memory, vision, the ability to recognise faces, chronic pain, motor function, even a sense of self. What lie in the background, glowing faintly, are the issues of medical science, the wonders it performs, the faith it inspires, and against that, its slowly diminishing but still 85 Ian McFfnnn vast ignorance of the brain, and the mind, and the relation between the two. Regularly penetrating the skull with some modest success is a relatively recent adventure. There's bound to be disappointment sometimes, and when it comes, the showdown with the relatives in his office, no one needs to calculate how to behave or what to say, no one feels watched. It pours out.

Among Perowne's acquaintance are those medics who deal not with the brain, but only with the mind, with the diseases of consciousness; these colleagues embrace a tradition, a set of prejudices only rarely voiced nowadays, that the neurosurgeons are blundering arrogant fools with b.u.m! instrument.-, bone-betters Jet Joose upon the most complex object in the known universe. When an operation fails, the patient or the relatives tend to come round to this view. But too late. What is said then is tragic and sincere. However appalling these heartfelt engagements, however much he knows himself to be maligned by a patient's poor or self serving recollection of how the risks have been outlined, whatever his certainty that he's performed in the theatre as well as current knowledge and techniques allow, Perowne comes away not only chastened - he has manifestly failed to lower expectations - but obscurely purified: he's had a fundamental human exchange, as elemental in its way as love.

But here on University Street it's impossible not to feel that play-acting is about to begin. Dressed as a scarecrow, in mangy fleece, his sweater with its row of holes, his paint stained trousers supported by a knotted cord, he stands by his powerful machine. He is cast in a role, and there's no way out. This, as people like to say, is urban drama. A century of movies and half a century of television have rendered the matter insincere. It is pure artifice. Here are the cars, and here are the owners. Here are the guys, the strangers, whose self-respect is on the line. Someone is going to have to impose his will and win, and the other is going to give way. Popular culture has worn this matter smooth with reiteration, this 86 ancient genetic patrimony that also oils the machinations of bullfrogs and c.o.c.kerels and stags. And despite the varied and casual dress code, there are rules as elaborate as the politesse of the Versailles court that no set of genes can express. For a start, it is not permitted as they stand there to acknowledge the self-consciousness of the event, or its overbearing irony: from just up the street, they can hear the tramping and tribal drums of the peace mongers. Furthermore, nothing can be predicted, but everything, as soon as it happens, will seem to fit.

'Cigarette?'

Exactly so. This is how it's bound to start.

In an old-fashioned gesture, the other driver offers the pack with a snap of the wrist, arranging the untipped cigarettes like organ pipes. The gripped hand extending towards Perowne is large, given the man's height, and papery pale, with black hair coiled on the back, and extending to the distal interphalangeal joints. The persistent tremor also draws Perowne's professional attention. Perhaps there's rea.s.surance to be had in the unsteadiness of the grip.

'I won't, thanks.'

He lights one for himself and blows the smoke past Henry who is already one point down - not man enough to smoke, or more essentially, to offer gifts. It's important not to be pa.s.sive. It has to be his move. He puts out his own hand.

'Henry Perowne.'

'Baxter.'

'Mr Baxter?'

'Baxter.'

Baxter's hand is large, Henry's fractionally larger, but neither man attempts a show of strength. Their handshake is light and brief. Baxter is one of those smokers whose pores exude a perfume, an oily essence of his habit. Garlic affects certain people the same way. Possibly the kidneys are implicated. He's a fidgety, small-faced young man with thick eyebrows and dark brown hair razored close to the skull. The mouth is set bulbously, with the smoothly shaved shadow of a strong beard adding to the effect of a muzzle. The general simian air is compounded by sloping shoulders, and the built-up trapezoids suggest time in the gym, compensating for his height perhaps. The sixties-style suit - tight cut, high lapels, flat-fronted trousers worn from the hip - is taking some strain around the jacket's single fastened b.u.t.ton. There's also tightness in the fabric round the biceps. He half-turns and dips away from Perowne, then bobs back. He gives an impression of fretful impatience, of destructive energy waiting to be released. He may be about to lash out. Perowne is familiar with some of the current literature on violence, it's not always a pathology; self interested social organisms find it rational to be violent sometimes. Among the game theorists and radical criminologists, the stock of Thomas Hobbes keeps on rising. Holding the unruly, the thugs, in check is the famous 'common power' to keep all men in awe - a governing body, an arm of the state, freely granted a monopoly on the legitimate use of violence. But drug dealers and pimps, among others who live beyond the law, are not inclined to dial nine-nine-nine for Leviathan; they settle their quarrels in their own way.

Perowne, almost a foot taller than Baxter, considers that if it comes to a sc.r.a.p he'll be wise to protect his t.e.s.t.i.c.l.es. But it's a ridiculous thought; he hasn't been in a hand-to-hand fight since he was eight. Three against one. He simply won't let it happen.

As soon as they've shaken hands, Baxter says, The expect you're all ready to tell me how sincerely sorry you are.' He looks back, past the Mercedes to his own car where it's parked at a diagonal across the road. Behind it is an irregular line, three feet from the ground, sc.r.a.ped along the sides of half a dozen parked cars by the BMW's door handle. The appearance on the street now of just one outraged owner will be enough to set off a cascade of insurance claims. Henry, knowing a good deal about paperwork, can already sense the prolonged trauma of it. Far better to be one of many victims than the original sinner.

He says, 'I am indeed sorry that you pulled out without looking.'

He surprises himself. This fussy, faintly archaic 'indeed' is not generally part of his lexicon. Deploying it entails decisions; he isn't going to pretend to the language of the street. He's standing on professional dignity.

Baxter lays his left hand on his right, as though to calm it. He says patiently, 'I didn't need to be looking, did 1? The Tottenham Court Road's closed. You aren't supposed to be there.'

Perowne says, 'The rules of the road aren't suspended. Anyway, a policeman waved me across.'

'Police man?' Baxter dividing and leaning on the construction makes it sound childish. He turns to his friends. 'You seen a police man?' And then back to Perowne, with mocking politeness, This is Nark, and this is Nigel.'

Until now, the two have stood off to one side, just behind Baxter, listening without expression. Nigel is the horse-faced man. His companion may be a police informer, or addicted to narcotics or, given his comatose look, presenting with narcolepsy.

'No policemen round here/ Nigel explains. 'They all busy with the marching sc.u.m.'

Perowne pretends to ignore both men. His business is with Baxter. This is the moment we swap insurance details.' All three chuckle at this, but he continues, 'If we can't agree on what happened, we'll phone the police.' He looks at his watch. Jay Strauss will be on court, warming up the ball. It's not too late to settle the matter and get on his way. Baxter hasn't reacted to the mention of a phone call. Instead, he takes the wing mirror from Nigel and displays it to Perowne. The spider web fissures in the gla.s.s show the sky in mosaics of white and ragged blue which 89 shimmer with the agitation in Baxter's hand. His tone is genial.

'Fortunately for you, I got a mate does bodywork, on the cheap. But he does a nice job. Seven fifty I reckon he'd sort me out.'

Nark rouses himself. There's a cashpoint on the corner.'

And Nigel, as though pleasantly surprised by the idea, says, 'Yeah. We could walk down there with you.'

These two have shifted their position so they're almost, but not quite, flanking Henry. Baxter meanwhile steps back. The manoeuvrings are clumsily deliberate, like an ill rehea.r.s.ed children's ballet. Perowne's attention, his professional regard, settles once again on Baxter's right hand. It isn't simply a tremor, it's a fidgety restlessness implicating practically every muscle. Speculating about it soothes him, even as he feels the shoulders of both men pressing lightly through his fleece. Perversely, he no longer believes himself to be in any great danger. It's hard to take the trio seriously; the cash idea has a boyish, make-believe quality. Everything said seems like a quotation from something they've all seen a dozen times before and half-forgotten.

At the sound of a trumpet expertly played, the four men turn to watch the march. It's a series of intricate staccato runs which end on a high tapering note. It might be a pa.s.sage from a Bach cantata, because Henry immediately imagines a soprano and a sweetly melancholic air, and in the background, a supportive cello squarely sawing away. On Gower Street the concept of a reproachful funereal march no longer holds. It was difficult to sustain with thousands in a column stretching over hundreds of yards. Now the chants and clapping rise and fall in volume as different sections of the crowd move past the junction with University Street. Baxter's fixed regard is on it as it pa.s.ses, his features faintly distorted, strained by pity. A textbook phrase comes to Henry in much the same way as the cantata melody - a modest rise in his adrenaline level is making him unusually a.s.sociative. Or the pressures of the past week won't release him from the habits, the intellectual game of diagnosis. The phrase is, a false sense of superiority. Yes, it can be down to a slight alteration in character, preceding the first tremors, somewhat short of, a little less disabling than, those other neurological conditions grandiosity, delusions of grandeur. But he may be misremembering. Neurology is not his field. As Baxter stares at the marchers, he makes tiny movements with his head, little nods and shakes. Watching him un.o.bserved for a few seconds, Perowne suddenly understands - Baxter is unable to initiate or make saccades - those flickering changes of eye position from one fixation to another. To scan the crowd, he is having to move his head.

As though in confirmation, he turns his whole body towards Perowne and says genially, 'Horrible rabble. Sponging off the country they hate.'

Perowne thinks he understands enough about Baxter to know he should get clear. Shrugging off Nigel and Nark at his side, he turns towards his car. T'm not giving you cash,' he says dismissively. T'm giving you my details. If you don't want to give me yours, that's fine. Your registration number will do. I'll be on my way.' He then adds, barely truthfully, T'm late for an important meeting.'

But most of this sentence is obliterated by a single sound, a shout of rage.

Even as he turns back towards Baxter in surprise, and even as he sees, or senses, what's coming towards him at such speed, there remains in a portion of his thoughts a droning, pedestrian diagnostician who notes poor self-control, emotional lability, explosive temper, suggestive of reduced levels of GABA among the appropriate binding sites on striatal neurons. This in turn is bound to imply the diminished presence of two enzymes in the striatum and lateral pallidum - glutamic acid decarboxylase and choline acetyltransferase. There is much in human affairs that can be accounted for at the level of the complex molecule. Who could ever reckon up 91 the damage done to love and friendship and all hopes of happiness by a surfeit or depletion of this or that neurotransmitter? And who will ever find a morality, an ethics down among the enzymes and amino acids when the general taste is for looking in the other direction? In her second year at Oxford, dazzled by some handsome fool of a teacher, Daisy tried to convince her father that madness was a social construct, a wheeze by means of which the rich - he may have got this wrong - squeezed the poor. Father and daughter engaged in one of their energetic arguments which ended with Henry, in a rhetorical coup, offering her a tour of a closed psychiatric wing. Resolutely, she accepted, and then the matter was forgotten.

Despite Baxter's impaired ocular fixation, and his ch.o.r.ea, those quick, jerky movements, the blow that's aimed at Perowne's heart and that he dodges only fractionally, lands on his sternum with colossal force, so that it seems to him, and perhaps it really is the case, that there surges throughout his body a sharp ridge, a shock wave, of high blood pressure, a concussive thrill that carries with it not so much pain as an electric jolt of stupefaction and a brief deathly chill that has a visual component of blinding, snowy whiteness.

'All right/ he hears Baxter say, which is an instruction to his companions.

They grab Henry by his elbows and forearms, and as his vision clears he sees that he's being propelled through a gap between two parked cars. Together they cross the pavement at speed. They turn him and slam his back against a chain locked double door in a recess. He sees on the wall to his left a polished bra.s.s plaque which says Fire Exit, Spearmint Rhino. Just up the street is a pub, the Jeremy Bentham. But if it's open this early, the drinkers are all inside in the warmth. Perowne has two immediate priorities whose importance holds as his full consciousness returns. The first is to keep the promise to himself not to fight back. The punch has already told him how much expertise he lacks. The second 92 is to stay on his feet. He's seen a fair number of brain injuries among those unlucky enough to fall to the ground before their attackers. The foot, like some roughneck hick town, is a remote province of the brain, liberated by distance from responsibility. A kick is less intimate, less involving, than a punch, and one kick never quite seems enough. Back in the epic days of organised football violence when he was a registrar, he learned a good deal about subdural haematomas from steel-tipped Doc Martens.

He stands facing them in a little whitewashed brick cave of a recess, well out of sight of the march. The structure amplifies the rasp of their breathing. Nigel takes a fistful of Perowne's fleece and with the other hand seeks out the bulge of his wallet which is in an inside zipped pocket.

'Nah,' Baxter says. 'We don't want his money.'By this Perowne understands that honour is to be satisfied by a thorough beating. As with the insurance claims, he sees the dreary future ahead. Weeks of painful convalescence. Perhaps that's optimistic. Baxter's gaze is on him, a gaze that can't be shifted unless he moves the whole of his heavy shaven head. His face is alive with small tremors that never quite form into an expression. It is a muscular restlessness that will one day - this is Perowne's considered opinion become athetoid, plagued by involuntary, uncontrollable movements.

There's a sense among the trio of a pause for breath, a steadying before the business. Nark is already bunching his right fist. Perowne notes three rings on the index, middle and ring fingers, bands of gold as broad as sawn-off plumbing. He has, he reckons, a few seconds left. Baxter is in his mid-twenties. This isn't the moment to be asking for a family history. If a parent has it, you have a fifty-fifty chance of going down too. Chromosome four. The misfortune lies within a single gene, in an excessive repeat of a single sequence - CAG. Here's biological determinism in its purest form. More than forty repeats of that one little codon, and 93 you're doomed. Your future is fixed and easily foretold. The longer the repeat, the earlier and more severe the onset. Between ten and twenty years to complete the course, from the first small alterations of character, tremors in the hands and face, emotional disturbance, including - most notably sudden, uncontrollable alterations of mood, to the helpless jerky dance-like movements, intellectual dilapidation, memory failure, agnosia, apraxia, dementia, total loss of muscular control, rigidity sometimes, nightmarish hallucinations and a meaningless end. This is how the brilliant machinery of being is undone by the tiniest of faulty cogs, the insidious whisper of ruin, a single bad idea lodged in every cell, on every chromosome four.

Nark is drawing back his right arm to strike. Nigel seems content to let him go first. Henry has heard that early onset tends to indict the paternal gene. But that may not be right. There's nothing to lose by making a guess. He speaks into the blaze of Baxter's regard.

'Your father had it. Now you've got it too.'

He has the impression of himself as a witch doctor delivering a curse. Baxter's expression is hard to judge. He makes a vague, febrile movement with his left hand to restrain his companions. There's silence as he swallows and strains forward, frowning, as if about to clear an obstruction from his throat. Perowne has expressed himself ambiguously. His 'had' could easily have been taken for a 'has'. And Baxter's father, alive or dead, might not even be known to his son. But Perowne is counting on Baxter knowing about his condition. If he does, he won't have told Nigel or Nark or any of his friends. This is his secret shame. He may be in denial, knowing and not knowing; knowing and preferring not to think about it.

When Baxter speaks at last, his voice is different, cautious perhaps. 'You knew my father?'

'I'm a doctor.'

'Like f.u.c.k you are, dressed like that.'

94 'I'm a doctor. Has someone explained to you what's going to happen? Do you want me to tell you what I think your problem might be?'

It works, the shameless blackmail works. Baxter flares suddenly. 'What problem?'

And before Perowne can reply, he adds ferociously, 'And you'll shut the f.u.c.k up.' Then, as quickly, he subsides, and turns away. They are together, he and Perovvne, in a world not of the medical, but of the magical. When you're diseased it is unwise to abuse the shaman.

Nigel says, 'What's going on? What did your dad have?'

'ShuI up.'

The moment of the thrashing is pa.s.sing and Perowne senses the power pa.s.sing to him. This fire escape recess is his consulting room. Its mean volume reflects back to him a voice regaining the full timbre of its authority. He says, 'Are you seeing someone about it?'

'What's he on about, Baxter?'

Baxter shoves the broken wing mirror into Nark's hands. 'Go and wait in the car.'

'You're kidding.'

The mean it. Both of you. Go and wait in the f.u.c.king car.'

It is pitifully evident, Baxter's desperation to separate his friends from the sharer of his secret. The two young men exchange a look and shrug. Then, without a glance at Perowne, they set off back up the road. Hard to imagine they don't think something is wrong with Baxter. But these are the early stages of the disease, and its advance is slow. They might not have known him long. And a jazzy walk, an interesting tremor, the occasional lordly flash of temper or mood swing might in their milieu mark out a man of character. When they reach the BMW Nark opens a rear door and tosses the wing mirror in. Side by side, they lean on the front of the car watching Baxter and Perowne, arms folded like movie hoods.

Perowne persists gently. 'When did your father die?'

95 Ian McEiuan 'Leave it.' Baxter is not looking at him. He stands fidgeting with shoulder turned, like a sulky child waiting to be coaxed, unable to make the first move. Here is the signature of so many neurodegenerative diseases - the swift transition from one mood to another, without awareness or memory, or f understanding of how it seems to others.

'Is your mother still alive?'

'Not as far as I'm concerned.' *

'Are you married?' m 'No.'

'Is your real name Baxter?'

That's my business.'

'All right. Where are you from?'

'I grew up in Folkestone.'

'And where do you live now?'

'My dad's old flat. Kentish Town.'

'Any occupation, training, college?'

'I didn't get on with school. What's that to do with you?'

'And what's your doctor said about your condition?'

Baxter shrugs. But he's accepted Perowne's right to interrogate. They've slipped into their roles and Perowne keeps going.

'Has anyone mentioned Huntington's Disease to you?'

A feeble dry rattling sound, like that of stones shaken in a tin, reaches them from the march. Baxter is looking at the ground. Perowne takes his silence as confirmation.

'Do you want to tell me who your doctor is?'

'Why would I do that?'

'We could get you referred to a colleague of mine. He's good. He could make things easier for you.'

At this Baxter turns and angles his head in his attempt to settle the taller man's image on his fovea, that small depression on the retina where vision is most acute. There's nothing anyone can do about a damaged saccadic system. And generally, there's nothing on offer at all for this condition, beyond managing the descent. But Henry sees now in Baxter's 96 agitated features a sudden avidity, a hunger for information, or hope. Or simply a need to talk.

'What sort of thing?'

'Exercises. Certain drugs.'

'Exercise . . .' He snorts on the word. He is right to pick up on the fatuity, the feebleness of the idea. Perowne presses on.

'What has your doctor told you?'

'He said there's nothing, didn't he.'

He says this as a challenge, or a calling in of a debt; rerowne's been reprieved, and in return he has to come up with a reason for optimism, if not a cure. Baxter wants his doctor proved wrong.

But Perowne says, 'I think he's right. There was some work with stem-cell implantation in the late nineties but 'It was s.h.i.t.'

'Yes, it was disappointing. Best hope now apparently is RNA interference.'

'Yeah. Gene silencing. One day perhaps. After I'm dead.'

'You're well up on this then.'

'Oh thank you, doctor. But what's this about certain drugs?'

Perowne is familiar with this impulse in patients, this pursuit of the slenderest leads. If there's a drug, Baxter or his doctor will know about it. But it's necessary for Baxter to check. And check again. Someone might know something he doesn't. A week pa.s.ses and there could be a new development. And when the line runs out in this field, the charlatans lie in wait for the fearful, offering the apricot-stone diet, the aura ma.s.sage, the power of prayer. Over Baxter's shoulder Perowne can see Nigel and Nark. They're no longer leaning against the car, but walking up and down in front of it, talking animatedly, gesturing up the road.

Perowne says, 'I'm talking about pain relief, help with loss of balance, tremors, depression.'

Baxter moves his head from side to side. The muscles in his cheeks are independently alive. Henry senses an 97 approaching shift of mood. 'Oh f.u.c.k/ Baxter keeps murmuring to himself. 'Oh f.u.c.k.' In this transitional phase of perplexity or sorrow, the vaguely ape-like features are softened, even attractive. He's an intelligent man, and gives the impression that, illness apart, he's missed his chances, made some big mistakes and ended up in the wrong company. Probably dropped out of school long ago and regrets it. No parents around. And now, what worse situation than this could he find himself in? There's no way out for him. No one can help. But Perowne knows himself to be incapable of pity. Clinical experience wrung that from him long ago. And a part of him never ceases to calculate how soon lie can safely end this encounter. Besides, the matter is beyond pity. There are so many ways a brain can let you down. Like an expensive car, it's intricate, but ma.s.s-produced nevertheless, with more than six billion in circulation.

Rightly, Baxter believes he's been cheated of a little violence and the exercise of a little power, and the more he considers it, the angrier he becomes. Another rapid change in mental weather, a new mood front is approaching, and it's turbulent. He ceases his murmuring and moves in close enough for Perowne to smell a metallic flavour on his breath.

'You streak of p.i.s.s,' Baxter says quickly as he pushes him in the chest. 'You're trying to f.u.c.k with me. In front of those two. You think I care? Well f.u.c.k you. I'm calling them back.'