He nods, but already I’ve given him too much information, and I can feel myself flushing with shame. He’s a Londoner, he doesn’t want to chat.

The trouble is, I want to talk to someone. I need to. A stranger, someone who I won’t see again.

I haven’t told my family I’m coming back tonight. Growing up with my mother, I learned long ago that the less you say, the less you get asked.

The one person I would like to confide in is being buried today, in the churchyard at St Mary’s, a tiny stone hut, so old people aren’t sure when it was first built. In the churchyard there is the grave of a customs officer, one of many kil ed by desperate smugglers. There is a lot about Cornwal that is stil kind of wild, pagan, and though the fish restaurants, tea shops and surfboards cover some of it up, they can’t entirely conceal it.

Granny believed that. She was from Cornwal , she grew up near St Ives, on the wild north coast. She saw Alfred Wal is painting by the docks, she was born with the cry of seagul s and the wind whistling through the winding streets of the old town in her ears. She loved the landscape of her home county; it was her life, her job. She lived most of her life there, did her best work there, sitting in her studio high at the top of the house, overlooking the sea.

There are so many things I never asked her, and now I wish I had. So often that I wished I could confide in her, about al sorts of things, but knew I couldn’t. For much as I loved my granny, I was scared of her too, of the blank look she’d get in her lovely green eyes sometimes when she looked at me. My husband Oli said once he sometimes thought she could see straight into your soul, like a witch. He was joking, but he was a little scared of her, and I know what he meant. There are some things you didn’t ask her. Some things she wouldn’t ever talk about.

Because for many years, Summercove was a very different place, centre of a glittering social whirl, and my grandparents were wealthy, successful, and it seemed as if they had the world at their feet. But then their daughter Cecily died, two months short of her sixteenth birthday, and my grandmother stopped painting. She shut up her studio, at the top of the house, and as far as I know she never went back. I learned from a very early age never to ask why. Never to mention Cecily’s name, even. There are no photos of her in the house, and no one ever talks about her. I know she died in 1963, and I know it was an accident of some kind, and I know Granny stopped painting after that, and that’s about it.

We’re going past Newbury, and the landscape is greener. There has been a lot of rain lately, and the rivers are swol en and brown under a grey sky. The fields are newly ploughed. A fast wind whips dead leaves over and around the train. I sit back and breathe out, feeling the nauseous knot of tension in my stomach start to slowly unravel, as a wave of something like calm washes over me. We are leaving London. We are getting closer.

Chapter Two

My grandparents met in 1941, at a concert at the National Gal ery. When the war broke out, Granny was nineteen, studying at St Martin’s School of Art in London. She stayed there, despite her parents demanding she return to Cornwal . Not Frances, oh no. She volunteered to man the first-aid post near her digs in Bloomsbury, she was fire watch officer for St Martin’s, and when she had a spare hour, which was not many, she went to the National Gal ery, around the corner from the col ege, to listen to Dame Myra Hess’s lunchtime concerts.

Arvind (we have always cal ed him that, Jay and I don’t know why except he’s not someone you’d ever think of cal ing ‘Grandad’, much less

‘Gramps’) was born in the ancient Mughal city of Lahore, in 1919. His father, a Punjabi Hindu, was a teacher at Aitchison Col ege, an exclusive school for sons of maharajahs and landowners, so Arvind was entitled to a place there. Arvind was bril iant. So bril iant that the headteacher wrote to various dignitaries, and to people in England, and after two years of studying philosophy at Lahore’s Government Col ege (there’s a photo of his matriculation on the wal of his study, rows of serious-looking young men with arms crossed and neat cowlicks), Arvind was given a postgraduate scholarship to Cambridge, and it was on a research trip to London during the height of the Blitz in 1941 that he wandered into the National Gal ery.

I have a very clear image of them in my mind; Arvind, short and dapper, so politely dressed in his best tweed suit, his umbrel a hooked over his arm, his hat clutched in his slender fingers, his eye fal ing briefly on the girl in front of him, watching the performance with total absorption. Granny was beautiful when she was old; when she was younger, she must have been extraordinary. I keep a photo of her from around that age in my studio: her dark blonde hair careful y swept into a chignon, her huge dark green eyes set in a strong, open face, a curling, smart smile, perfect neat white teeth.

Frances and Arvind were married three months later. Bizarrely for a man who has outlived most of his contemporaries, Arvind was told he had a weak heart and couldn’t fight. He went back to Cambridge and finished his degree, where he and several other students were cal ed upon to try a variety of code-breaking formulae. He also knitted socks – he rather took to it, he liked the patterns – and volunteered for the Home Guard. Granny stayed in London, to finish her studies and carry on driving the ambulances.

Though Granny and Arvind never said anything, I often wonder what her parents must have made of it. They were respectable quiet people who rarely left Cornwal , with an elder daughter who had recently become engaged to a solicitor from a good family in Tring, and suddenly their wild, artistic younger daughter writes from a bomb shelter to let them know she’s married a penniless student from India whom they’ve never met. This was seventy years ago. There was no one from France, let alone the Punjab, in Cornwal .

After Granny and Arvind were married, they rented a tiny flat in Redcliffe Square. Mum and Archie, the twins, were born in 1946 and then a couple of years later, Cecily. Money was tight, Granny’s painting and Arvind’s writing did not bring in much; he was writing his book for years, paying the bil s with teaching jobs. The book became something of a joke after a while, to al of them, so the aspect of their married life that always took them by surprise, I think, is the money that came in when The Modern Fortress was final y published, in 1955. It argued that post-war society was in danger of reverting to a complacency and ossification that would lead to another world war of the magnitude of the one we had only just barely survived. It was translated into over thirty languages and become an instant modern classic, debated and argued over by mil ions, fol owed ten years later by The Mountain of Light, which initial y sold even more, though it is now seen as the more ‘difficult’ of the two books. When I was fifteen, we had to read The Modern Fortress for GCSE History, as part of the course was about post-WW2 Europe. I am ashamed to say I understood not very much of it; even more ashamed to say I didn’t tel the teacher at school that Arvind Kapoor was my grandfather. I don’t know why.

While The Modern Fortress was sel ing thousands of copies a week, Granny’s paintings were becoming more acclaimed too and suddenly Frances and Arvind were richer than they’d ever expected to be.They could afford to buy the house they’d rented for a couple of summers in Cornwal for Frances to paint in, a dilapidated twenties art deco place by the sea cal ed Summercove. They could send the children to boarding school. They could keep the flat in London and a housekeeper for Summercove, and they could have their nieces and nephews to stay, and provide a degree of largesse to al they knew that meant, for the rest of the fifties and the early sixties, Arvind Kapoor and Frances Seymour, and Summercove, were bywords amongst artistic and intel ectual circles in London for an elegantly bohemian way of life, post-colonial poster children: the couple that seemed to have everything.

* * *

In Granny’s bedroom at Summercove, there is a curved dark wooden dressing table, with a beautiful enamel hairbrush set, old glass crystal perfume bottles and two jewel ery boxes. The dressing table has little drawers with wrought-iron handles on each side, and once when I was little and I’d crept upstairs to surprise her, I found my grandmother sitting at that table, gazing at a photo.

She was very stil , her back straight. Through the long suntrap windows you could see across the meadow down to the path, the bright blue-green sea glinting in the distance. I watched her as she stared at the photo, stroking it with her finger, tentatively, as if it had some talismanic quality.

‘Boo,’ I’d said softly, because I didn’t know what else to do, and I knew it wasn’t right to jump out at her now. I didn’t want her to be angry with me.

She did jump though, and she turned to me. Then he held out her hand. ‘Oh. Natasha,’ she said, as I stood looking at her.

I adored my grandmother, who was beautiful, funny, charis matic, in charge of everything, always in control: I found her hugely comforting, thril ing too, but the truth is she was also a little terrifying. Compared to her happy, open relationship with Jay, I felt sometimes, just sometimes, she looked at me and wished I wasn’t there. I don’t know why. But children like me – with an overactive imagination and no one with whom to exercise it

– are often wrong. And I knew that if I ever tried to talk to my mother about it she’d tel me I was making things up, or worse, confront Granny, and have a row with her.

‘Come here,’ she said, looking at me, and she smiled, her hand outstretched. I walked towards her slowly, wanting to run, because I loved her so much and I was so glad she wanted me. I stood in front of her and put my hands on her lap, tentatively. She stroked my hair, hard, and I felt a tear drop from her eyes onto my forehead.

‘God, you’re just like her,’ she said, her voice husky, and clutched my wrist with her strong fingers. She twisted the fingers of her other hand over to show me the photo she was holding. It was a smal , yel owing snap of a girl about my age; I was then around seven or eight. I wish I could remember more, because I think it was important. I remember she had dark hair, but of course she did, we al did. She looked like Mum, but also not: I couldn’t work out why.

‘Yes, you’re just like her.’ Granny drew a great shuddering breath, and her grip on my arm tightened. ‘Damn it al .’ She turned, her huge green eyes swimming with tears, her lovely face twisted and ugly. ‘Get out! Get out of here, now!’

She was stil gripping my arm, so hard it was bruised the next day. I wrenched myself free and ran away, feet clattering on the parquet floor, out onto the lawn, away from the dark, sad room. I didn’t understand it, how could I?

Later, when we were having tea and playing hide-and-seek, she came up and gave me a hug.

‘How’s my favourite girl?’ she said, and she dropped a soft kiss onto my forehead. ‘Come here, let me show you this brooch I found in my jewel ery box. Do you want to wear it tonight, at supper with the grown-ups?’

I didn’t know it then, but I saw a side of her that day that she rarely showed anyone any more. She kept it locked away, like the photo, like her studio. I tried to push it out of my mind that summer, and when I got back to London. And now. It’s not the way I want to remember her.

We are heading further and further west, the landscape is wilder, and though spring feels far away, there are tiny green buds on the black branches fringing the railway tracks. We go through southern Somerset, past Castle Cary and the Glastonbury Tor. I stare out of the window, as if wil ing myself to see more.

Oli and I went to Glastonbury last summer, because of his job – one of his clients gave us VIP tickets, with backstage passes. We were very lifestyle that weekend – I wore my new Marc Jacobs city shorts and some Cath Kidston polka-dot wel ies, Oli was in his best Dunhil shirt: we felt like a low-rent Kate Moss and Jamie Hince. We saw Jay-Z, and Amy Winehouse, and the Hoosiers, who I love but Oli thinks are crap. It was great, of course, although I remember going in a camper van when I was nineteen with Jay and my best friend Cathy, the year of the legendary Radiohead gig, not washing for three days and being stoned the whole time, and that was better somehow, less complicated, no one in a mood, no one looking dissatisfied because there are only two free beers in the wanky hospitality tent where everyone’s terrified they’re less important than everyone else. Oli complained when they wouldn’t give him another one. Oh, Oli.