As the heavy car moved through the London-bound traffic I began to read the questionnaires which Vaughan had prepared. The subjects who had completed the forms represented a cross-section of Vaughan's world: two computer programmers from his former laboratory, a young dietitian, several airport stewardesses, a medical technician at Helen Remington's clinic, as well as Sea-grave and his wife Vera, the television producer and Gabrielle. From the brief curriculum vitae elicited from each subject I saw, as I expected, that they had all at some time been involved in a minor or major automobile crash.

In each questionnaire the subject was given a list of celebrities from the worlds of politics, entertainment, sport, crime, science and the arts, and invited to devise an imaginary car-crash in which one of them might die. Scanning the list offered, I saw that most of the figures were still alive; a few were dead, some of these in auto-crashes. The names gave the impression of having been picked at random from a quick recall of newspaper and magazine headlines, television newscasts and documentaries.

By contrast, the choice of wounds and death-modes available showed all the benefits of an exhaustive and lingering research. Almost every conceivable violent confrontation between the automobile and its occupants was listed: mechanisms of passenger ejection, the geometry of kneecap and hip-joint injuries, deformation of passenger compartments in head-on and rear-end collisions, injuries sustained in accidents at roundabouts, at trunk-road intersections, at the junctions between access roads and motorway intersections, the telescoping mechanisms of car-bodies in front-end collisions, abrasive injuries formed in roll-overs, the amputation of limbs by roof assemblies and door sills during roll-over, facial injuries caused by dashboard and window trim, scalp and cranial injuries caused by rear-view mirrors and sun-visors, whiplash injuries in rear-end collisions, first and second-degree burns in accidents involving the rupture and detonation of fuel tanks, chest injuries caused by steering column impalements, abdominal injuries caused by faulty seat-belt adjustment, second-order collisions between front-seat and rear-seat passengers, cranial and spinal injuries caused by ejection through windshields, the graded injuries to the skull caused by variable windshield glasses, injuries to minors, both children and infants in arms, injuries caused by prosthetic limbs, injuries caused within cars fitted with invalid controls, the complex self-amplifying injuries of single and double amputees, injuries caused by specialist automobile accessories such as record players, cocktail cabinets and radiotelephones, the injuries caused by manufacturers' medallions, safety belt pinions and quarter-window latches.

Lastly came that group of injuries which had clearly most preoccupied Vaughan – genital wounds caused during automobile accidents. The photographs which illustrated the options available had clearly been assembled with enormous care, torn from the pages of forensic medical journals and textbooks of plastic surgery, photocopied from internally circulated monographs, extracted from operating theatre reports stolen during his visits to Ashford hospital.

As Vaughan turned the car into a filling station courtyard the scarlet light from the neon sign over the portico flared across these grainy photographs of appalling injuries: the breasts of teenage girls deformed by instrument binnacles, the partial mammoplasties of elderly housewives carried out by the chromium louvres of windshield assemblies, nipples sectioned by manufacturers' dashboard medallions; injuries to male and female genitalia caused by steering wheel shrouds, windshields during ejection, crushed door pillars, seat springs and handbrake units, cassette player instrument toggles. A succession of photographs of mutilated penises, sectioned vulvas and crushed testicles passed through the flaring light as Vaughan stood by the girl filling-station attendant at the rear of the car, jocularly talking to her about her body. In several of the photographs the source of the wound was indicated by a detail of that portion of the car which had caused the injury: beside a casualty ward photograph of a bifurcated penis was an inset of a handbrake unit; above a close-up of a massively bruised vulva was a steering-wheel boss and its manufacturer's medallion. These unions of torn genitalia and sections of car body and instrument panel formed a series of disturbing modules, units in a new currency of pain and desire.

The same conjunctions, all the more terrifying when they seemed to evoke the -underlying elements of character, I saw in the photographs of facial injuries. These wounds were illuminated like medieval manuscripts with the inset details of instrument trim and horn bosses, rear-view mirrors and dashboard dials. The face of a man whose nose had been crushed lay side by side with a chromium model-year emblem. A young coloured woman with sightless eyes lay on a hospital couch, a rear-view mirror inset beside her, its glassy stare replacing her own vision.

Comparing the completed questionnaires, I noticed the differing accident modes selected by Vaughan's subjects. Vera Seagrave's choices had been made at random, as if she had barely distinguished in her mind between windshield ejection, roll-over and head-on collisions. Gabrielle had emphasized facial injuries. Most disturbing of all the replies were Seagrave's – in the crashes he devised the only wounds his hypothetical victims suffered were severe genital injuries. Alone among Vaughan's subjects, Seagrave had selected a small target gallery of five film actresses, ignoring the politicians, sportsmen and television personalities whom Vaughan had listed. On these five women – Garbo, Jayne Mansfield, Elizabeth Taylor, Bardot and Raquel Welch – Seagrave had built an abattoir of sexual mutilation.

Horns sounded ahead of us. We had reached the first heavy traffic in the approaches to the western suburbs of London. Vaughan drummed impatiently on the steering wheel. The scars on his mouth and forehead formed a clear hatchwork in the afternoon light, the marking areas of a future generation of wounds.

I turned the pages of Vaughan's questionnaires. The photographs of Jayne Mansfield and John Kennedy, Camus and James Dean had been marked in coloured crayons, pencil lines circled around their necks and pubic areas, breasts and cheekbones shaded in, section lines across their mouths and abdomens. Jayne Mansfield stepped from her car in a studio publicity still, left leg on the ground, right thigh raised to reveal the maximum of its inner surface. Her breasts were thrust forward, below an engaging come-on smile, and almost touched the canted door pillar of the wrap-around windshield. One of the interviewees, Gabrielle, had marked imaginary wound sites on her left breast and exposed thigh, a section line in coloured crayon across her throat, outlining those parts of the car which would marry with her body. The free areas around these photographs were covered with annotations in Vaughan's scrawled handwriting. Many ended with a question mark, as if Vaughan were speculating about alternative death modes, accepting some as plausible and rejecting others as too extreme. A faded agency picture of the car in which Albert Camus had died was elaborately re-worked, the dashboard and windshield marked with the words 'nasal bridge', 'soft palate', 'left zygomatic arch'. An area in the lower section of the instrument panel was reserved for Camus' genital organs, the dials covered with cross-hatching and provided at the left margin with a key: 'glans penis', 'scrotal septum', 'urethral canal', 'right testicle'. The fractured windshield opened on to the crushed bonnet of the car, an arcade of fractured metal revealing the engine and radiator, together covered by a long V-shaped swathe in a dotted white tint: 'Semen'.

At the conclusion of the questionnaire the last of Vaughan's victims appeared. Elizabeth Taylor stepped from her chauffeured limousine outside a London hotel, smiled across her husband's shoulder from the depths of a rear seat.

Thinking of this new algebra of leg-stance and wound area which Vaughan was calculating, I searched her thighs and kneecaps, the chromium door frames and cocktail cabinet lids. I assumed that either Vaughan or his volunteer subjects would have mounted her body in any number of bizarre postures, like a demented stunt driver, and that the cars in which she moved would become devices for exploiting every pornographic and erotic possibility, every conceivable sex-death and mutilation.

Vaughan's hand took the file from me and returned it to his briefcase.

The traffic had come to a halt, the access lanes to Western Avenue jammed by the first rush-hour traffic exiting from the city. Vaughan leaned against the window-sill, fingers raised to his nostrils as if clinging to the last odour of semen on their tips. The warning headlamps of the oncoming traffic, and the overhead lights of the expressway, the emblematic signals and destinations, lit up the isolated face of this hunted man at the wheel of his dusty car. I looked out at the drivers of the cars alongside us, visualizing their lives in the terms Vaughan had defined for them. For Vaughan they were already dead.

Six lanes wide, the traffic edged forward to the Western Avenue interchange, in this huge evening rehearsal of its own death. Red tail-lights flared like fireflies around us. Vaughan was holding passively to the rim of his steering wheel, staring with an expression of defeat at the fading passport photograph of an anonymous middle-aged woman clipped to the ventilation duct of the instrument binnacle. As two women walked along the road verge, cinema usherettes about to go on duty in their green braided uniforms, Vaughan sat up and scanned their faces, his eyes intent as a waiting criminal's.

As Vaughan stared at them I looked down at his semen-stained trousers, excited by this automobile marked with mucus from every orifice of the human body. Thinking of the photographs in the questionnaires, I knew that they defined the logic of a sexual act between Vaughan and myself. His long thighs, hard hips and buttocks, the scarred muscles of his stomach and chest, his heavy nipples together invited the countless injuries waiting among the protruding toggles and instrument heads of the car interior. Each of these imaginary wounds was the model for the sexual union of Vaughan's skin and my own. The deviant technology of the car-crash provided the sanction for any perverse act. For the first time, a benevolent psychopathology beckoned towards us, enshrined in the tens of thousands of vehicles moving down the highways, in the giant jetliners lifting over our heads, in the most humble machined structures and commercial laminates.