Three characters meet a grisly end in PD James’s new novel, The Private Patient. During its writing, she came close to death herself. While recovering from a hip replacement in Oxford last autumn, she visited her dentist and had heart failure. “Lying on my back, I suddenly couldn’t breathe,” she tells me, in the same crisp, collected tones in which her books recount even their most alarming events. “My friend who was with me took me in her car at great speed to her GP — she knew she couldn’t get to the hospital because it was Friday night and the roads were blocked. She drove very fast down bus lanes and, I think, saved my life. The GP came out to the car and put me on oxygen. He tested to see how much there was in my blood, which was not much. He got an ambulance straight away, and I went into the John Radcliffe.”

A long recuperation followed, which, with characteristically robust resourcefulness, she put to productive effect. A private room in a convalescent hospital proved the perfect environment in which to complete a novel about dark deeds in a private clinic. “It was a happy period of writing because all the problems seemed to disappear. It was very peaceful. No telephone. No visitors. The over-bed table served as a desk. I moved it from the bed and sat down in the high chair, quite comfortable, and there I was — writing away.”

Cheerfully turning even a brush with mortality to advantage is typical of James. Refusing to be daunted by misfortune is a lifelong trait. At one point, she declares: “I think a writer needs as much trauma as he or she can take.” It’s a remark that might seem to ring oddly amid the comforts of her home in Holland Park, where we meet just before her 88th birthday. The living room is pleasantly shaded. On one of the sage-green walls hangs a Regency painting bought because it reminds her of a scene from her favourite author, Jane Austen. Family photos (she has two daughters, five grandchildren and seven great-grandchildren) throng small tables. Next to the excellent coffee and shortbread lies a helpfully provided CV that modestly outlines what has been, by any standards, a remarkable career: notable service in the NHS and Home Office, an OBE and a life peerage (since 1991, she has been Baroness James of Holland Park), president of the Society of Authors, a governor of the BBC, chairman of the Arts Council’s Literature Advisory Panel, recipient of numerous honorary degrees, fellowships and crime-writing awards, author of 15 acclaimed and immensely popular detective novels, two non-crime novels, a volume of autobiography and a co-written book about a series of brutal murders in 19th-century Wapping. Published on September 1, her 16th detective novel, The Private Patient, is poised, like most of its predecessors, to scale the bestseller list. Yet inside its pages are indications that James is a writer as familiar with trauma as with success.

Unusually for her, this novel was inspired not by a place, but by an out-of-the-blue image of a woman with a scar. Rhoda Gradwyn, as she became, is a journalist who bears the scar of an injury inflicted during an unhappy childhood. Most of the book’s other figures have endured bleak infancies, too, as have many of James’s characters.

Does this reflect her own childhood experience? “I was a child of a marriage that was not entirely satisfactory or very happy,” she says. “My parents were so different.” Her father, who worked for the Inland Revenue, was highly intelligent, but “not easy or comfortable in human relationships. He was never cruel, but authoritarian. Looking back, I feel there was a high level of apprehension — apprehension of disapproval, of some awful tragedy happening. I think there was a lot of anxiety there. I always felt that”.

Her warm-hearted, unintellectual mother had a breakdown and was committed to “a grim Victorian asylum, where I would visit with my father. That was traumatic and went on for quite a long time”. James, then 14 or 15, had to help run the house and look after her younger siblings.

A sign that this premature responsibility was coming to an end still glows in her mind. Entering her bedroom after a neighbour had been employed as housekeeper, she saw her nightdress ironed and laid out to air in the sunshine on the windowsill. “There was a sense of being looked after, which was very comforting.”

At 16, she left Cambridge High School, where she had thrived. While working as a “dogsbody” at Cambridge’s Festival Theatre, she met Connor Bantry White, a medical student. In 1941, they married and moved to London, where they enjoyed “a very happy time”. (“Because it was the time of the bombing, it seems funny to say that, but there was a great camaraderie.”) Medical students were often employed as fire watchers. “There were almost nightly parties at the top of the building,” James recalls. “There we were, with stirrup pumps and buckets of sand. Everybody would congregate.”

She wasn’t frightened until the V-1 and V-2 rockets came. She was then awaiting the birth of her second daughter and staying with friends in Hampstead, where “the racket was appalling, because the V-1s and V-2s were so noisy, and on Hampstead Heath were anti-aircraft guns”. To blot this out, she reread Austen by torchlight in the basement. “What a comfort to be able to retreat into her world — and, of course, when the baby was born, she was named Jane.”

Her stress didn’t ease. When Connor (who had joined the Royal Army Medical Corps and served in India and Africa) returned after the war, he became ill — with some form of schizophrenia, she thinks. “He was in and out of hospitals. People always thought they could do something, but never could.” When he was home, “it was hard, very, very hard. He’d be all right for a while, then there was a big explosion, as it were”. Because of their father’s illness, the children went to boarding school “very young”, but “never lost their affection for him, nor he his affection for us”. Her continuing affection is audible as she speaks of how he “loved reading. He had great charm. He was a very dear, very sweet man”. For almost two decades, working for the NHS, she held things together, until, in 1964, he died at home.

In 1968, she applied to the Civil Service and, having come third in the country in the qualifying exam, was offered a choice of department. She opted for the police, later switching to criminal law. Was she aware how useful this would be to a crime-fiction writer? “You bet. It was an absolute gold mine.” NHS experience (administrating five psychiatric clinics, especially) also proved invaluable.

As a child, James had not only been keen to write, but had a tendency to question others’ stories (her mother thought her “very cynical”), indicative of a budding crime novelist. Famously, when she first heard of Humpty Dumpty, she asked: “Did he fall or was he pushed?” At Sunday school, she doubted the two disciples who walked to Emmaeus with Christ could have failed to recognise him, as surely his voice and mannerisms would have given the game away.

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