Harry Keller had had a fascination with trains since as long as he could remember. As a child, he had lived in a house overlooking a major junction and marshalling yard in the English Midlands, and now he was fifty-two, nostalgic for the steam giants of his youth, he took holidays aboard railway trains, travelling long journeys through six continents. He had organised his holidays around themes, ranging from studying wildlife, to visiting remote tribes and fishing communities, and sampling Chinese culture.

So far, a theme or objective for this years wanderings had not presented itself. What he finally settled on — not a very highbrow plan either, for once — popped into his mind after lunch with one of his sons with whom he kept in fairly close touch. Young Roddy, nineteen and full of testosterone and self-confidence, had just come back from his own holiday.

'So did you spend all your time on the beach?' asked Harry.

'Some of it. Then clubs and bars in the evening.'

'Meet any girls?'

Roddy grinned. 'Quite a few. There's something about being on holiday in Ibiza when you're young... '

'There's something about being on holiday at any age, ' Harry said.

Roddy eyed the grey stubble, the incipient wrinkles and the un-trendy, non-designer clothes worn by his father. He snorted with derision. 'Oh, sure!'

'Do you think your generation is the first to experience the loosening effect of holidays on knicker elastic?'

Roddy sniggered.

'I suppose you can't imagine me as a sexual being?'

'No.'

'But you know how many children I have — your four half-sisters and three half-brothers. Eight. Not bad for an old man. But then, I wasn't always old. Actually, I'm not that old now.'

'Just decrepit!' Roddy grinned. Harry aimed a gentle swipe at his head, which his son had no problems avoiding.

Later in the day, when Roddy had gone back to work, Harry recalled their conversation. He had had many adventures in his youth, and six of his children had different mothers, whilst two were twins, son and daughter of a seventh. As a successful artist, he had enjoyed relationships with most of his models, and in seven cases, pregnancies had resulted. These had not been his only sexual forays, but — as far as he knew — no lasting consequences had arisen from any other.

It had once bothered him that there had been so many children, but the days had been heady and hedonistic, art had been exciting, and making love to his models — or at least those who had been willing — had seemed part of it, a fine conclusion to a portrait. Somewhere in his mind, he had been aware that he had avoided the responsibilities of fatherhood, but neither had he ever been asked to provide financial support for the children and their mothers. Six of the children knew him for their natural father, and he had a good relationship with them; the twins' mother had married and preferred to keep him out of her life, and her children's. It hadn't occurred to him that he might have found full-time parenthood rewarding, and that it was an opportunity missed. But it had occurred that while he had been undeniably poor in his youth, he had been equally undeniably selfish.

Wryly, he found himself wishing he still had the vigour of his youth, but on reflection, there was something to be said for the experience which comes of being fifty-two. After all, he was very confident that any woman he might take to bed at this stage of his life would leave it well satisfied — possibly more so than when he was twenty. That was when the idea for this year's holiday came to him: in all his time travelling, he had never had sex on a train. That would be his objective.

A month later, rucksack slung across his shoulders, he waited to board the Eurostar at Waterloo. It had taken some effort to plan his trip: after all, the glittering modern Eurostar would not present any thematic opportunities, and in any case, some of the European trains were much more romantic. He'd avoided the temptation to travel on the Orient Express because it had featured in highly unlikely tales by Ian Fleming and Agatha Christie, and instead would use slower but possibly more romantic alternatives.

Once in Paris, he made his way on foot, over-ground, from the Gare du Nord to the Gare de Lyon. On the long straight route of the Boulevard de Magenta, he became aware of the click of heels on the pavement behind him, neither approaching nor receding. He paused for a moment, and glanced in a window, using it as a mirror to spot whoever was keeping pace.

A woman in a black leather coat and sunglasses hesitated just long enough for Harry to know she was the follower, before she walked past him, keeping her face straight ahead. Fifty metres along the street, she, too, paused at a window. Intrigued, Harry walked up to her.

'Bonjour, m'amoiselle.'

'Hello, Harry, ' she said in a resigned tone, turning to him.

'Hello. Have we met?'

She pushed the sunglasses up into her hair. With an artist's practised eye, he noted the symmetry of her face, the cheekbones and almond eyes, the short, almost retroussé nose, and the eminently kissable lips. A memory surfaced.

'I'm Natasha Mayland.'

One of the relationships which had not resulted in children, as far as he could now recall. He smiled.

'Of course. How very nice to meet you again. You are still as paintable as you were, what, fifteen years ago?'

She grinned faintly. 'About that. You've aged, but like a lot of men, you look even better with silver hair and a more lived-in face. It's more than you deserve, for breaking my heart.'

She had walked out on him, when it became clear that he had no plans to marry her. But before then, he recalled that the sex had been very good. She had been a kind-hearted woman, and he hoped she had found a man worthy of her. The suggestion that he had broken her heart he did not take very seriously.

'Are you living in Paris, now?'

'No, I came on the Eurostar, like you. I thought I recognised you when you got on board. I don't quite know what made me follow you down the street.'

'I guess I should hesitate before suggesting fond memories?'

She smiled. 'You remember, then?'

'How could I forget?' he said, with more charm than veracity.

She seemed to have run out of small talk, and there was silence between them for a moment. Then she leaned against a shop-front for balance while lifting one leg and grabbing her foot.

'My shoe is pinching me.'

'Shall we find a place to sit and perhaps have a drink for old times' sake?'

They looked around and spied an umbrella and a few chairs marking a brasserie in a small street leading off the boulevard. They walked arm in arm, at a comfortable pace, and sat at one of the small round tables. A distracted youth, wearing earphones, a red T-shirt and green apron attended them. Harry ordered a pastis for himself and a lemonade for Natasha.

Natasha lifted her foot and grasped the ankle. Harry without thinking cupped her heel in the palm of one hand, and unfastened the strap with the other. She withdrew her hands to rest on her hips, and allowed him to remove her shoe, and rest her foot comfortably on his thigh. He massaged the tender flesh of her instep, and between the toes, during which processes his hands slid along the smooth flesh of her calf from time to time.

She laid back in the chair as far as she could, sliding her bottom as far forward on the seat as possible, so that her foot crossed Harry's lap, and her knee was now centred above his groin. Beneath the table, she slipped the other shoe off, and lifted her other leg until it lay beside the first.

'Mm, that's nice, Harry. You haven't lost your touch.'

'You have very beautiful legs, my dear. I remember painting them.'

'You admired them at the time, too, Harry. And they were not all of me you liked.'

'You are as beautiful now as you were then. Fifteen years have left not a mark on you.'

She raised an eyebrow at this declaration.

'I didn't have wrinkles fifteen years ago. If you can't remember that, and spot the differences between then and now, you've lost your touch.'

Harry looked up at her face and leaned forward until he could reach it, cupping her face in his fingers, and smoothing the cheek with his thumb.

'You are every bit as beautiful as you were — and I remember you perfectly. You have no wrinkles I can see.'

She moved her head out of his reach. 'You're losing your eyesight, Harry, but selectively, it seems.'

The waiter returned with their drinks. Harry paid him, adding a generous tip. His hands rested back on her knees, which had moved apart to allow his fingers to slip between them. One foot began pressing rhythmically on his groin, and he was beginning to notice the effect it had on him. He slid his hands up and down her nylon-covered legs, discovering, to his delight, that she wore stockings, not panty-hose. Suddenly he stopped.

'Just what are we doing, Natasha?'

'We are two old and dear friends, sitting outside a brasserie in Paris, enjoying a drink in the sunshine, and you are running your hands up and down my legs.'

'And you are doing amazing things with your foot. Shall we find a place where we can relax, and which isn't quite so public?'

'You'd better bring a bottle of wine with you. Where?'

Harry had heard that there were many hotels in Paris which rented out rooms by the hour, but had no knowledge of any, personally. Then again, a hotel room by the hour was not what Natasha deserved. He called a taxi, and followed her inside.

'Hotel George Cinq, ' he ordered, and the taxi driver made every attempt to get there at the speed of light. During the brief journey, while their enthusiastic chauffeur cheated death at several junctions, treating the shouted criticisms from other drivers with commendable sang-froid, Harry continued his fingertip examination of Natasha's knees. They arrived at the impressive portal of one of Paris' most prestigious hotels.

Glared at by a Commissionaire of great self-importance, they made their way to the reception desk, where they were condescendingly granted the favour of a room on the top floor, with a view which stretched several metres to a windowless brick wall bounding the hotel's service yard several storeys below. Harry figured he'd been lucky to get the room, considering the fact that his clothing reflected casual comfort rather than Parisian elegance and sophistication. He thanked God for the instinct which the French had for a couple in urgent need of a bed.

He phoned for a bottle of wine, a bottle of Romanée Saint-Vivant, which was quite extravagant but he was feeling good. Natasha decided to have a shower while they awaited the bottle's arrival.

A waiter, this time dressed in the livery of the George V, no headphones in sight, knocked at the door and was admitted, carrying the bottle and two glasses. He went through the little ritual of displaying the label, then removing the foil cap and opening the bottle with a few deft twists of his corkscrew. He poured a table-spoonful into one of the glasses, which Harry held to the light. Then, swilling the wine round the inside of the bowl, he dipped his nose within to savour the bouquet. Satisfied, he nodded, and the waiter filled the glass. Harry asked him to leave the bottle, and, bestowing a douceur on the man, let him out of the room. He took the opportunity to hang the 'do not disturb' sign on the handle before closing the door.

Sipping wine, he explored the room, whilst waiting for Natasha to finish her shower, completing his tour by the window, when, some time after the shower stopped, he heard the door open and turned to watch her as she came into the room. He was intrigued that she still wore her black leather coat and stockings, and had put her shoes on again.

Harry crossed to the table, and poured a glass of wine for her. He noticed that the coat was not fastened: she was holding it across her with one hand, whilst holding the glass with the other. She drank appreciatively. Harry smiled.

'Wine okay?'

'Very good. Rather better than the supermarket special you used to buy to seduce your models.'

'Natasha!' he exclaimed in injured tones.

She raised an eyebrow at him. 'Well, isn't it?'

He acknowledged the truth of her assertion. 'I suppose you're right.'

She looked round the room: the ceiling, the walls, the window, the carpet, the bed. She settled herself on an antique couch with silver silk quilted cushions.

'I wish you wouldn't keep using this word "seduce", ' he said. 'It sounds as though I am some sort of Lothario. I never set out to seduce you — or anyone else. When we made love, it just sort of ... happened.'

She glanced at him sceptically. 'I suppose you think staring at a nude female all day, with a bulge in your trousers, doesn't count as seduction.'

'Uh, if that's what I did, then no.'

'I found it extremely flattering — and arousing, if you must know. Rather like what you were saying and doing at the brasserie an hour ago.'

'Whatever you call it, it worked, ' he said with a grin. He sat opposite her in a matching chair.

'Did you ever get married?' she asked.

He spread his long, slender fingers and shrugged. 'No. Never quite got round to it. And besides, who would I have chosen?'

'Out of so many!'

He laughed ruefully. 'Aye, that's true. I was never good material for a husband, or a life partner. There was always another pretty girl on the horizon.'