Not for the first time he had linked his own last accident to my exhibition, implying that I had served as the catalyst for his erratic driving. But, if anything, the exhibition had been inspired by David. I remembered him hunting the streets of London, driving in the same dangerous way that he had practised for the first time on the long, straight road from Moose Jaw to the air base. At the demolition derbies in the shabby stadiums of east London he and Sally had willed themselves towards death.

One-way streets excited them to play a desperate roulette. Late one evening, two years after the exhibition, David had driven the wrong way down the westward lane of the Hammersmith flyover, headlamps flashing as he forced the oncoming cars against the safety rail. A middle-aged cellist and her husband, confused by the siren of the pursuing police car in the parallel carriageway, had failed to stop in time. The wife had been killed over her steering wheel, and only David’s deranged behaviour after his arrest and his active RAF service in Kenya had saved him from a manslaughter charge.

Under a section of the Mental Health Act he had been sent, first, to the special custody unit at Rampton, and then to Summerfield for observation. Six months later, as he crouched with his largactil shudders in this sunlit room filled with entranced and grumbling women, the memory of the cellist’s death still pushed at the door of his mind. I felt nothing but concern for him and his younger self, now the same age as Henry, who had emerged from his Japanese camp into the postwar world. David had understood my needs but failed to read his own. He had tried, hesitantly at first, to re-create the cruelty he had known in wartime China, not realising that the postwar world was only too keen to do this for him. The psychopath was saint.

When I first visited him at Summerfield he had said, setting out the rules of our relationship: “Remember, Jim—all I did on the flyover was what you did in your exhibition…”

Now the casualties of the sixties were coming home, to the veterans’ hospitals, the mental institutions, and the private clinics. In a drawing room above a cold Scottish lake Sally Mumford was measuring out her days in methadone. When I telephoned her she sounded flat but rested, unlike the confused and hyper-irritable woman who had arrived at Shepperton one evening two months earlier, needing my help but refusing to speak to me. Fortunately the children had been away, staying with their aunt. I tried to sleep on the sofa as Sally spent the night weeping and striding around the empty bedrooms, ransacking the cupboards for old toys which she stuffed into her bag.