Flora and Jonathan were reading in bed when he made the announcement. Two evenings a week, until further notice, he would be running home from the office. She laughed once, curtly, like spitting.

‘That’s really,’ she said, ‘really quite far. Why not work up to it? We could go around the park on Saturday.’

He pointed out that she ran only on weekdays, preferring to avoid ‘weekend wobblers’. Surprised by how mean this phrase of hers sounded, she shook two multivitamins out, swallowed one and, indulging a habit that would prove tenacious even long after he was gone, held the other out for him to take.

‘I wouldn’t mind together,’ she said. Tablet glow lit her face, scrubbed clean of make-up and doused with lotion. Reading glasses perched on her long nose – she only wore them around the house. On her nightstand lay a hand-tooled notebook for the recording of important nocturnal thoughts. The most recent entry – Celeriac? – was several weeks old.

He wasn’t looking for a personal trainer, he said, just telling her not to expect him, supper-wise, much before nine. He leafed through the latest Monocle. His pyjamas, patterned with tiny bicycles though it was twenty-plus years since he’d ridden one, had been purchased and wrapped by Flora as a gift from their eldest daughter, Annabel.

‘Supper-wise,’ she said, pleased at least by the sound of the word. In the thriller she was reading, a man in a woolly hat just had cut out a woman’s tongue. Now Flora’s tongue felt enormous in her mouth, enormous and wonderful. ‘New voice on your phone today?’

She’d called around eleven to pass on the news of their middle child’s third detention this term, as reported in an email from the head. Since Sally had never been any trouble before she went off to Millfield, and since Flora had begged Jonathan not to send her away – for the girl’s own good, supposedly, though in truth her motives were more selfish than that – she was really calling for vindication. The new PA – Melissa was her name – had seemed talkative and incompetent, promising so emphatically to pass on the message that Flora had been sure she’d forget.

In the end, they’d had the detention chat getting into bed, Jonathan receiving the news with a smirk. Flora looked across to see him staring at a perfume ad, bringing the page to his nose for a sniff. She could smell his last cigarette of the day. His hair seemed greyer than the last time she’d looked – how unfair that it only improved a man. Her own would need doing soon, not that he’d notice unless she shaved it all off or coloured it pink like that Spanish girl at Nero. Imagine. The look on his face.

She ran first thing, empty stomach, any weather, for the purity, the monastic rhythm – so she told other mothers when they said they’d seen her in the park. In fact, she rarely braved the rain. With Jonathan gone before she even woke up, she lingered with Charlie in the kitchen, watching his cartoons, wolfing sugary fistfuls of his preferred cereal straight from the box. He had a way of looking at her, half accusing and half amused, silver eyes narrowed, smiling with the left side of his mouth. Our secret, she told him, though even the boy didn’t know that once he left for school she poured a deep bowlful for herself. So kind of you to share, she told him. Those early minutes were the day’s best, Charlie’s orange curls still flat from his pillow, and she knew that when Jonathan tried to send him away too, she would fight like a lioness to keep him home.

Once the Frosties had been eaten, she had no choice but to run. The artificial sweetness, fuzzy tongue and aching teeth, the delicious surge of guilt propelled her out into the street.

She ran without music, O-shaped water flask gripped in fist. Her shoes, so comfortable that to remove them was unpleasant, had cost nearly two hundred pounds. According to the treadmill at Runners Need, they were perfectly suited to the way she landed – heavily on the heel’s outside edge. She wore them for days at a time, to the bakery, the deli, the fishmonger’s, even to Nero with Zoe.

‘This morning,’ Zoe said, flawless in black leather jacket and heeled knee-high boots, ‘I stood in front of the mirror and thought, who are you even dressing up for?’

But then Flora watched as the good-looking young waiter gave her friend a pain au chocolat on the house – the pink-haired girl looked sullenly on – and as outside a white van executed an emergency stop so Zoe could cross the road. Flora watched the three men in the van watch her friend, then went home and called the salon. Later, ashamed by the shoes but unwilling to change, she cancelled the appointment with minutes to spare.

She ran alone, trying to land more lightly on her heels, hearing the air pile into her lungs and billow out again, hearing the metronomic thud of her pulse. Along the Fulham Road, past the bookshop and the cinema, down to the river, where the light changed and the sky opened up, over Battersea Bridge past stationary buses with glum faces turned to the windows, east into the park, dewy grass and glistening leaves. She ran laps, past the lake and tennis courts, past the Peace Pagoda which every woman in Chelsea just loved.

Zoe was so funny about that.

Two laps was four miles, and by now she felt it in her knees and hips, not fatigue or pain so much as what their Pilates teacher called the limitations of her body. Honour, the teacher said, feet behind head. Honour and disobey.

The city had always looked best when she was moving. She’d never forgotten the train ride down from Durham, after graduation in 1993 – the way it all finally rose up at the window, like men pushing back their chairs to stand as she came into a room. A guy across the aisle had chatted her up, said he worked at Radio 4. She’d wanted so badly to believe him. Soon she was doing publicity at one of the big houses, pouring wine at launches, sending out bound proofs. She kept a toothbrush and a fresh pair of knickers at the office for the nights she didn’t make it home. Jonathan she met in the spring – his PR agency had the Booker contract. The third time they spoke, he asked if she was seeing anyone. That he checked was disappointing, and she said yes to test him. He was seven years older – the perfect gap, she thought.

They married within a year, in Guernsey at Torteval parish church, close to her parents’ house. A tussle broke out at the reception, and one of her cousins was dragged outside, chin slick with blood. When Annabel was born in the autumn, the girls from work sent flowers – We miss you! Come back ASAP! Sweet of them to say, Jonathan said. Nothing came, though, when Sally or Charlie arrived. Most of them were having children of their own by then, but she couldn’t help picturing them all squeezed around a table at The Fox & Goose, sinking pints and filling ashtrays, cackling.

For her thirtieth birthday, he took her to Paris, her first time on the Eurostar. Only when the train plunged into the darkness did she realize she’d imagined a clear, aquarium-style tunnel. The disappointment was terrible, though what had she possibly expected to see? She kept it to herself. Later, at a noisy Montmartre bistro, waited on by a girl so effortlessly stunning she was like a blade cutting through the smoke, Flora drank too much wine and missed the children so badly she could hardly eat. At the hotel, she fell asleep, still in her blue dress and shoes, Jonathan out on the balcony smoking, calling the view tremendous.

Every summer since Charlie was born, she had taken all three of them to Guernsey for a fortnight. Her parents’ house had only three bedrooms, so there were fold-out cots wherever you looked. Jonathan joined them reluctantly for a long weekend in the middle, blaming the briefness on work. Last year, after eight straight days of rain, Annabel had declared that she wouldn’t be going again. She wanted to go away with her friends, to their family villas in Tuscany and Mallorca, no doubt to sneak out into the Continental night and be kissed and touched by beautiful, dark-haired boys. Flora knew she should understand. Besides, at fifteen the girl grew less and less pleasant to be around. But it had always seemed important that her children know and love the island of her own youth, even if the place had felt suffocating to her by the time she’d reached that age herself. She couldn’t help equating their loss of interest in the island with a loss of interest in her. She wanted them to know the world beyond their capsule of privilege, or at least to know that free things were valuable too. Cliff walks over Petit Bôt, crabbing at Portelet, camping in Herm – some things she remembered more clearly than others, but even the parts she never thought of at all were in her somewhere, doing their work, like vitamins, like a breath.

‘Trying to impress her?’ Zoe said. ‘Or something more sinister?’

Flora cut her pastry into four equal parts and put one in her mouth. Outside the café window, February rain came down. ‘He staggers in, head-to-toe running gear, gasping, straight into the shower. Eats whatever I put in front of him, glass and a half of red, cigarette and into bed. I’ve never known him fall asleep so fast.’

Zoe shook her head. ‘I told Brian on our honeymoon that if he ever cheated on me, I’d cut off his dick with a steak knife. It helped that I had it in my hand at the time.’

‘The knife?’

‘Last night he told me apropos of literally nothing that his high-school sweetheart used to swallow.’

Zoe had met Brian at Syracuse. He’d wound up at Goldman’s, and after the crash had been transferred over the pond, their son Jude soon appearing in Charlie’s class. Seven years younger than Flora, Zoe had made no friends and complained frequently about Chelsea women. ‘You wouldn’t believe how that snooty bitch looked at me . . .’ Sometimes she developed elaborate schemes to get back at whoever had pissed her off – inviting them over for brunch, say, then cancelling, rescheduling, cancelling again. Flora, who had told Jonathan many times that she wished they’d never left Clapham, understood. She was fond of the American to an extent that made her nervous, in the same way that as a schoolgirl she’d been reluctant to designate a best friend without first being selected herself. She’d read somewhere that an only child will often struggle to make people laugh. Knowing this had suddenly seemed to make it true.

‘Not your style?’ she said, chewing.

Zoe gave her a look. ‘Oh, we have a system. Bri taps me on the shoulder at the last second and I dive out of the way.’

Flora nodded. ‘I never minded, personally.’

Zoe loved that.

After coffee they went into the bookshop. Isaac, behind the counter, knew her name and waved – apologetically, she always thought.

‘Anything new and spectacular?’ she would say, at least once a week. She never left without a hardback biography, an obscure translated novel, some poetry. These went unread on to the dining-room shelves – she’d get to them one day, or not. Her trick was to covertly browse the thrillers, photographing one or two with her phone for downloading later on the tablet. Isaac hated tablets and she never mentioned hers, instead telling him stories of her working days – riding in a taxi with Amis and Hitchens, booking flights for Barnes. About himself, Isaac gave little away. He was twenty-eight or so, she guessed, a frustrated poet, sharing a poky Streatham flat with an old friend. That day he sold Flora a coffee-table book of war photography. ‘Oh, Bill Pointer,’ she said. The name was vaguely familiar. ‘Yes, of course.’

‘You should seduce him,’ Zoe said, back outside. ‘Show the poor kid the ropes.’

For a moment, Flora was stunned by the image – on her knees behind the counter, sweaty in her running shoes, customers browsing obliviously as Isaac poured himself into her mouth. She blinked it away, shifted the heavy book bag from one shoulder to another.

‘I just love it when you blush,’ Zoe said, touching Flora’s cheek.

She had a long-held belief that she was hard to embarrass. Unflappable. When she was seventeen, the big joke at Ladies’ College had been inspired by her namesake margarine and a rumour no one would confess to starting. Flora spreads easily. The teasing hadn’t bothered her – in fact she had relished the status it conferred. 1989, year of the drought. Early in the summer, a young family had moved in next door. Along with his rust-brown lawn and dead hydrangeas, her father had moaned daily about the noise the two boys made playing out in the long, warm evenings.

She’d been seeing a scaffolder called Natty, mostly because other girls were doing something similar and it had become a sort of unacknowledged slumming competition. Meredith – everyone called her Fauna – had recently lost her virginity to a bricklayer with Satan My Saviour tattooed calligraphically across his shoulders, describing the experience as ‘lush’. Natty was tattoo-free but drove a lowered Golf GTI with booming speakers in the back. He called her Floz or, sometimes, Flozzie.

She’d spoken to Roger, the new man next door, once or twice over the fence. He seemed afraid of her, something Natty definitely wasn’t, and she found herself thinking of him at odd times. While showering, for example, or clipping her nails. He had a nervous, effeminate way of fussing with his hair when he talked. Once, clearing up after a barbecue, she’d heard the wife shouting hysterically, his only response a series of sullen mumblings.

One weekend in early September, her parents went to Saint-Malo. I’ve asked Roger to keep an eye on you, her mother said, his wife’s away too so he’s got his hands full, don’t bother him unless you have to. She didn’t tell Natty the house was empty – there’d been some disastrous parties – so that night he drove her out to the moorings at Saints. She watched him pour Smirnoff into a half-empty Coke and smoke a B&H while she drank it. His hair was buzzed so short on the sides she could see his pale scalp. He pulled her over, kissed her briefly, pushed her head down. Roger appeared again in her mind, paintbrush adorably in hand, cowering like a puppy on his roof that morning as the Red Arrows had roared overhead. She pushed back hard against Natty’s hand, sat up and asked to be taken home.

Back on Jerbourg Road, as the Golf sped away and she fumbled tearfully for her keys, she saw Roger through his living-room window, alone on the sofa. His long hair, even wilder than usual, seemed to have paint in it. He looked boyish, sitting hands and knees together like that. In need of reassurance. She clattered up the driveway to knock on the door.

When at last he opened up, the telephone was ringing. His eyes were wide as he ushered her in and went into the kitchen to answer the call. Alone in the living room, she looked around, tipsy on the vodka but composed. That morning, sunbathing in the garden, she’d caught him watching her from up on his roof as he painted the chimney or whatever he was doing. Now she saw white paint all over the carpet, thickest on the granite slabs where the fireplace should have been. The fumes were dizzying – had he dropped the pot down the chimney or something? Half-empty boxes were strewn around, furniture carelessly arranged. She could hear him on the phone but not what he said. The house was structurally like hers but shabbier, worse. She went into the little bathroom by the back door. In the mirror she saw that her mascara had run.

She found him standing as if lost in his own living room. ‘Hello, mister neighbour.’

He turned. ‘Flora, are you all right?’

Everything felt cosy and innocent. Outside the sky was losing light, the day’s heat fading. She put her arms around him and after a moment he did the same. Neither let go and then he was inhaling the smell of her hair and touching his lips to her forehead. She felt him grow hard against her hip and even that was endearing, nothing like with Natty. She pressed herself against him, turned her mouth up to his.

He tasted like salt and vinegar, like chip-shop chips. Also a bit of wine. Her tongue felt bigger than his, though surely it couldn’t be. After a while, she pushed him gently back on to the sofa. His hands lay flat, palms down against the cushion, as if he were steadying himself. As she knelt, thinking before she even began that she would never be able to tell anyone about this, footsteps sounded through the ceiling.

Roger leaped up instantly, bumping her forehead with his hip. He led her, almost dragged her, towards the front door. As he opened it, though they didn’t meet hers, she saw fear in his eyes. Before it closed behind her, she heard a child’s voice at the top of the stairs say, ‘Daddy? Are you there?’

Then she was in her own house, in a better-decorated replica of the hallway from which she’d just been expelled, expecting to cry but grinning instead, spinning like a dancer to the fridge for some milk.

‘You must have seen him all the time,’ Zoe said. They were in her kitchen, mid-afternoon, leaning against the polished granite worktops, drinking Sauvignon blanc. Radio 4 was on, a man’s voice declaring that the protests in Tahrir Square left Egypt’s prime minister with no option but to resign.

‘We moved later that year, thank God. But I did see him a few years back, on the beach. He looked so old. Must be nearly sixty now.’

‘You spoke?’

‘Christ, no. I was with the kids. He recognized me, though, I’m sure. He looked at Annabel like she was a ghost.’

‘Is this what you wanted to tell me? Because we’ve all made our married-man-mistakes.’

Flora shook her head.

‘Uh oh.’

Zoe refilled their glasses.

‘Last night, I ran out of garlic,’ Flora said, ‘right at the crucial moment. Dashed out to Sainsbury’s and what do I see? Jonny. Getting out of a cab in his running gear and jogging off up Beaufort Street with his pathetic little backpack.’

Zoe’s eyes were fascinated. ‘He sees you?’

Another headshake. ‘Next thing I know I’m flagging down the cab, saying fifty quid to go once round the block if you tell me where you picked my husband up and exactly what he said. He thinks about it – these bastards – but when I show him the cash he says, “Crouch End. Said name any great man in history, they all had at least one mistress.” Apparently his examples were Napoleon, JFK and some old Brazilian footballer.’

‘Napoleon? Are you kidding me?’

Flora shrugged. ‘This morning I call his office and have a nice little chat with this Melissa. Guess where she tells me she lives?’

Zoe threw her arms up, spilled her wine. Flora watched her wipe off the worktop, the white tiles. Then her friend went quiet for a while, and Flora could see she was having one of her ideas.

It took a few days and dozens of calls each. With only ten weeks to go, all places had long been filled, but Zoe was sure there had to be a charity willing to bend the rules for the right price.

A woman called Victoria proved to be the one. She had a girl at Millfield too, and had been to Guernsey once for the Battle of Flowers. Pleasant enough, she said, if you like that sort of thing. Victoria represented Cancel Cancer, whose runners had to raise at least five thousand each. No, she had no objection to a direct donation. None whatsoever.

‘When do I tell him?’ Flora asked later at Pilates. They were stretched out on purple mats, surrounded by limbs and grimaces.

‘Oh, not for a while,’ Zoe said. The pleasure of plotting was all over her face. ‘We don’t actually want him getting in shape, right?’

‘I suppose not.’

In her thrillers, it was always a girl being murdered or mutilated by a man. The formula should have got boring, but it never did. Still, she’d often thought, why not switch it around? Months later, after the funeral, when the condolence cards had been stuffed in a drawer, when Zoe and Brian had moved back to the States (to Westchester, to work on their marriage, whatever that meant) and Charlie had passed the Millfield entrance exam, she would remember this moment – how her hamstrings felt tight, how the teacher looked exhausted. She would wonder how differently things might have turned out if she’d never met Zoe at all.

She bought a new pair of the same shoes and a special watch that monitored her heart rate. When Isaac said he was sure she’d do fine, she detected him glancing down at her body, assessing her machinery. From him she bought books on marathon training that she hid under the bed, consulting them only when alone. On her tablet she bought apps to track her progress, plot her routes.

She ran laps of the park, one more each time. She ran the river, all the way to Greenwich and back or out to Richmond or Wimbledon, in miserable drizzle or perfect blue stillness, further every week. On the South Bank, she weaved through dawdling tourists, imagining how she must look to them – woman of the city, solitary, adamant, unconstrained by timetables and maps. At Canary Wharf, towers swaying overhead, she heard in her mind the spectacular noise of the hordes who would gather on race day, cheers ringing out down the glassy canyons. London itself re-emerged as she ran, parading and presenting itself as it had when she’d first arrived, almost twenty years ago now, dragging two suitcases up the King’s Cross escalators. You can do this, she told herself, a word for each stride, over and over, you can do this, you must, you will.

Honour and disobey, Zoe said.

Finally, with six weeks to go, she told him. He was in his robe, fresh out of the shower, eating curry she had made from scratch. He froze, loaded fork hanging. She sat opposite, thighs throbbing from that morning’s nine miles, watching the twitch of panic.

‘Us?’ he said. ‘Did you say entered us?’

She smiled. ‘I’m so proud of you.’ The words that Zoe had scripted for her fell a little woodenly out of her mouth. ‘All this running! You’re so much happier, so energetic. You’re –’ She faltered. ‘You’re like a new man.’

He stared at her, then down at his plate. She could see it seeping in. His jaw swelled by his ears as he ground his teeth.

‘Do you know what yesterday was?’ she said, off script now. She saw his eyes widen. ‘Sixteen years. All I want’ – he tried to interrupt, but she raised a hand and went on – ‘all I want is to do this together. No jewellery, no restaurant, no fucking perfume. This.’

Upstairs, Charlie yelled in triumph at a video game. Before Jonathan could answer, she reached across, hand a little shaky, picked up his glass of red and went, sipping, to tell her son to get ready for bed.

Greenwich Park teemed with people. Eight in the morning, grey cloud, fine drizzle settling in. Under a yellow awning they congregated with other Cancel Cancer runners, everyone stretching, pacing on the spot, chattering nervously. She tied and retied her shoelaces, Jonathan pale and silent nearby. They had run together only a handful of times, he gasping and limping beside her. Earlier that week, after running home from work – apparently determined, despite it all, to maintain that particular pretence – he’d paused as he struggled up the stairs, one hand gripping the banister, the other at his throat. She’d watched him from the sofa, the big book of harrowing photographs she’d bought from Isaac open on her lap, willing him to call to her so she could go to him.

They joined the stream of runners approaching the start. Many wore flimsy clear ponchos for the rain. Jonathan said, ‘We don’t have ponchos why?’

People all around them wished each other luck. Several were in costume – nurses, vampires, Supermen, some wearing shoes like hers. Music pounded from speakers draped with plastic sheeting, while, at the railings, spectators cheered and clapped. Zoe would be on The Mall with Jude and Charlie later to watch them enter the home straight. But all that was more than four hours off.

They passed under the gate and everyone began to run. Excitement flooded her limbs – she could go for fifty miles, a hundred, more.

‘For Christ’s sake slow down,’ Jonathan hissed.

After the first heady rush, they fell into a rhythm. They were out on the south-eastern edge of the city – Woolwich, Charlton, Westcombe Park – bleak residential tracts she had never seen. The crowd out there was thin, locals strung along the rain-soaked pavements giving desultory yelps of support. She’d been warned to expect this of the first half. Later the noise would be incredible, along the Embankment with the end in sight, all those miles behind her, the raucous stands strewn with banners and flags.

They ran side by side in marital silence, passing or being passed. Every thirty seconds, he hawked and spat. She heard his breathing over her own, glimpsed the pain on his face. The giddiness had faded, but still she felt strong, no more strained than if she were walking. The rain came down harder, relentless and cool.

They passed the six-mile marker after seventy-five minutes, back at Greenwich Park, heading west along the northern edge, less than a mile from where they began. Six of twenty-six. She felt his mood darken.

After Sally had arrived, when Flora had been trapped at home all day with a baby and a toddler, Jonathan’s agency had merged with another. He worked all hours, travelled most weeks. Adrift in those housebound afternoons, she wondered where her life had gone – nights in The Fox, endless parties, the sense of being exactly where she belonged. This was in Clapham, before the move across the river. She’d grown convinced he was having an affair, something he denied again and again – you’re losing it, he told her, you’re stewing in these silly ideas. Later, she realized the girl she’d pictured was a teenaged version of herself, the room littered with boxes and spilled white paint. She wondered now whether by accusing him and staying she had given him a kind of permission.

Fuck that, Zoe would say.

Twenty-six miles. It occurred to her, suddenly, that that was as long as the coastline of Guernsey. Nine miles up, five across, twenty-six around – numbers she would never forget. But her island felt like another world now. And could she really call it hers any more? She had left it behind, that was the truth. Best thing she ever did.

He wheezed now, arms limp, shoes scuffing the tarmac. ‘Go on if you want,’ he said. She shook her head, but she wanted to run faster, to surge ahead into the wide Westminster streets, the roar of the waiting crowds, Zoe’s face there among all the others.

‘Yes,’ he said, panting, nodding. ‘Go, go.’

She jogged at his side, low houses reeling past, knowing she should say something. Instead she reached out and squeezed his hand until she felt him squeeze back. Then she let go and she was driving with her arms, kicking up her legs, faster and faster until she was sprinting, the space between them opening up. She was passing people half and twice her age, girls in tiny skin-tight shorts, hairy-shouldered men, two walking bearded angels who soon enough would be kneeling over him there on the tarmac, plastic wings flapping as they pounded on his chest and tried to pass air from their lungs into his.

Extracted from Exactly What You Mean by Ben Hinshaw, published by Viking on 24 March 2022. Copyright © Ben Hinshaw 2022