It was difficult to decide how conscious this behaviour was. Sometimes I thought she was highly manipulative; other times I saw her as a victim, isolated and alienated by circumstance. Peter, who knew her as well as anyone, compared her to a feral cat-selfsufficient and unpredictable, with sharp claws. It was a fanciful analogy, but fairly accurate, since the goal of Winterbourne Barton appeared to be to “tame” her. Nonconformists may be the bread-and-butter of the media, and loved by the chattering classes, but they’re singled out for criticism in small communities.

Over time I heard Jess described as everything from an “animal rights activist” to a “predatory lesbian”-even “having an extra chromosome” because of her flat features and wide-spaced eyes. The Down syndrome charge was clearly nonsense, but I was less sure about the animal rights and lesbian tags. She was at her most animated when I asked her about the birds and wildlife in the valley, always able to identify animals from my descriptions and occasionally waxing lyrical on their habitats and behaviour. I also wondered if her twice-daily visits were a form of courtship. To avoid wasting her time, I made it abundantly clear that I was heterosexual, but she was as indifferent to that as she was to hints about leaving me alone.

After a couple of weeks, I was close to locking the doors, hiding the Mini in the garage and pretending to be out. I’d learnt by this time that I’d been singled out for special favours, since she never visited anyone else, not even Peter, and I began to wonder if Lily had found her as oppressive as I did. One or two people suggested that Jess’s attachment was to Barton House, but I couldn’t see it myself. I thought Peter’s suggestion that she saw me as a wounded bird was a more likely explanation. In her strangely detached way, she appeared to be monitoring me for signs of renewed anxiety.

Surprisingly, I didn’t show any. Not at the beginning, at least. For some reason, I slept better alone in that echoing old house than I had in my parents’ flat. I shouldn’t have done. I should have jumped at every shadow. At night the wisteria tapped on the window-panes and the moon silhouetted finger-like tendrils against the curtains. Downstairs, the numerous French windows invited anyone to break in while I slept.

My way of dealing with that threat was to leave the internal doors open and keep a powerful torch beside my bed. The beauty of Barton House was that every bedroom had a dressing-room with its own door to the landing, which meant I had a second exit if a prowler came along the corridor. It also had two staircases, one at the front and one at the back leading down to the scullery. This gave me confidence that I could outwit any intruder. I sprayed Jess’s WD40 into every external lock on the ground floor, and embraced the doors and windows as escape routes rather than entry points.

Nevertheless, it was Winterbourne Valley that was the real healer. The contrast between the noise and chaos of Baghdad and these peaceful fields of ripening corn and yellow rapeseed couldn’t have been greater. Passing cars were few and far between and people even scarcer. From the upstairs windows I could see all the way to the village in one direction and to the Ridgeway-a fold of land behind Dorset’s coastline-in the other. This gave me a sense of security for, even though the hedgerows and darkness would screen a trespasser, those same concealments would hide me.

JESS WAS A DEDICATED CONSERVATIONIST. Apart from her hostility to social change, she farmed her land in much the same way as her ancestors had done by scrupulously rotating her crops, rationing pesticides, stocking rare breeds and protecting the wild species on her property by conserving their natural habitats. When I asked her once what her favourite novel was, she said it was The Secret Garden by Frances Hodgson Burnett. It was a rare piece of irony-she knew I’d identify her immediately with the difficult, unloved orphan of the story-but the landscape of the hidden wilderness was certainly one she liked to inhabit.

By contrast, Madeleine liked her landscapes populated. She was at her best in company, where her easy charm and practised manner made her a popular guest. Peter described her as the typical product of an expensive girls’ boarding-school, well-spoken, well-mannered and not overburdened with brains.

I thought her extraordinarily attractive the first time I met her. She had the sweet face and cut-glass English accent of the elegant British movie stars of the forties and fifties, like Greer Garson in Mrs. Miniver or Virginia McKenna in Carve Her Name with Pride. It was the second Sunday of my tenancy. Peter had asked me along to meet some of my new neighbours over drinks in his garden. It was very casual, about twenty people, and Madeleine arrived late. I believe she came uninvited, as Peter hadn’t mentioned her beforehand.

Despite the photograph on the landing at Barton House, I had no idea who she was until we were introduced. Indeed, I’m sure I assumed she was Peter’s girlfriend, because she tucked her hand through his elbow as soon as she arrived and allowed him to lead her about the garden. His guests were genuinely pleased to see her. There was a lot of hugging and kissing, and cries of “How are you?” and I was slightly taken aback to discover this was Lily’s daughter.

“Your landlady,” Peter said with a wink. “If you have any complaints, now’s the time to make them.”

I’d been doing rather well up until then-with only the odd flicker of anxiety when I heard a male voice behind me-but I felt a definite lurch of the heart as I shook Madeleine’s hand. If Jess was to be believed, she was a callous bitch who had driven her mother into penury and then neglected her. My personal view was that Jess’s unaccountable hatred clouded her thinking, but the doubt was there, and Madeleine read it in my face.

Her immediate response was contrition. “Oh dear! Is the house awful? Aren’t you happy?”

What could I do, other than reassure her? “No,” I protested. “It’s beautiful…just what I wanted.”

There was nothing artificial about the smile that lit her face. She removed her hand from Peter’s elbow and tucked it into mine. “It is beautiful, isn’t it? I adored growing up there. Peter tells me you’re writing a book. What’s it about? Is it a novel?”

“No,” I said cautiously. “It’s non-fiction…a book on psychology…not very exciting, I’m afraid.”

“Oh, I’m sure it is. My mother would have been so interested. She loved reading.”

I opened my mouth to dampen her enthusiasm but she was already talking about something else. I don’t remember what it was now, a reference to Daphne du Maurier, I expect-“an old friend of Mummy’s”-whom she trotted out to new acquaintances as a close family connection. This seemed a little unlikely to me, as there was a considerable age difference between the novelist and Lily, and du Maurier had been dead for fifteen years, but Madeleine brushed such details aside. In the world she inhabited, meeting a person fleetingly at a party amounted to friendship.

She dropped names for effect in the same way that her mother was said to have done. I began to understand this when I commented on the paintings at Barton House and learnt that Nathaniel Harrison was her husband. It made sense of Jess’s remark that Madeleine had acquired the collection by sleeping with the man who owned them-even if “married to the artist” would have been more illuminating-but it led to a definite withdrawal on Madeleine’s part.

She spoke of Nathaniel as if he were up with greats, and to cement the impression she quoted David Hockney, suggesting he was a close acquaintance and a great admirer of her husband’s work. To listen to her, Hockney was a regular visitor to Nathaniel’s studio and always singing his praises to critics and dealers. I was genuinely interested, not just in how they knew Hockney, but in why he would champion an artist whose style and approach to painting were so different from his own.