Fiona married. Tessa, neglected and insecure, floated away; a victim of Fiona's career-making and her father's indifference. Poor Tessa, what might she have been if Fiona had guarded her and advised her and given to her according to her need?

'Are you all right?' Tessa called from the next room.

I'm coming, Tessa. It will all be all right. I promise you, I'll sort it out.'

Tessa came to her. 'I knew you would, Fi.' She threw her arms round Fiona's neck and kissed her. 'Dearest, darling, wonderful Fi, I knew you would.'

Such displays of affection embarrassed Fiona, but she stood stiff and still and put up with it.

Had the invitation to see Silas come in other circumstances, Fiona Samson would have enjoyed every minute of the weekend she spent with her husband and children at Whitelands, the farming estate to which Silas Gaunt had retired. His six hundred acres of the Cotswolds provided superlative walks and breath-taking views across the mighty limestone plateau that borders the shining River Severn.

But in this context everything was fraught with worries and dangers. Dicky Cruyer, the enterprising German Desk Controller, and his arty wife Daphne were there. Bret Rensselaer had brought a young blonde girl. Diffident in the company of so many strangers, she clung tight to him; so tight in fact that they'd arranged to have the only two bedrooms with a connecting door. Fiona guessed that Bret had requested those two rooms when she asked Silas if she could have the two children next to her, and Silas had replied that there were other needs greater than hers, and laughed.

Silas was a pirate, or at least he looked the part. A huge pot-bellied ruffian with a jowly face surmounted by a huge forehead and bald head. His baggy clothes were of high quality but he preferred old garments – as he preferred old wine and old friends – and displayed the faded patches and neat darns that were the work of his faithful housekeeper Mrs Porter, as an old warrior his medals.

The house itself was made of local stone, a lovely tan colour, and the furnishings – like the family portraits obscured behind murky coach varnish and the superb early eighteenth-century dresser – were in appropriate style. Silas Gaunt liked the dining room, especially when it was crowded, as it was this Saturday lunchtime. Gaunt stood at the head of the lovely Georgian mahogany table, carving an impressive beef sirloin for his professional cronies: the Samsons, Tessa, the Cruyers, Bret Rensselaer, and dominating them by the force of his personality.

Fiona Samson watched it all with a feeling of detachment. Even when her son Billy spilled gravy down his shirt, she only smiled contentedly, as if it was an incident depicted in an old home movie.

She watched the Cruyers with interest. Fiona had been at Oxford at the same time as Dicky. She remembered seeing him being cheered to victory at the debating society, and his making a pass at her that day when he was celebrating his cricket blue. One of the brightest of the bright boys at Balliol, he'd got the German Desk for which Bernard had been shortlisted and there was talk that he'd get the Europe job when the time came. Now she wondered if Silas Gaunt was going to propose that he was made a party to her secret. She hoped not: already enough people knew, and if Dicky was to be told while Bernard was kept in ignorance she would find it intolerable. Dicky noticed her looking at him and smiled at her in that shy manner that he'd found so effective with the Oxford girls.

She looked too at Tessa. Her husband George Kosinski was away. It was typical of Silas, and his luck and intuition, to guess that Tessa was connected with the phone call and to go to the trouble of inviting her in case he needed to know more.

When, after lunch, Silas took the men into the billiards room with a trayful of cigars and brandy, Fiona took Billy and Sally upstairs to do their homework.

'In leap year, Mummy, do ladies ask men to marry them?' said Sally.

'I don't think so,' said Fiona.

'My teacher said they do,' said Sally, and Fiona realized she had walked into the sort of trap Sally was fond of setting for her.

'Then teacher is no doubt right,' she said.

'It was Miss Jenkins,' said Sally. 'Daddy said she is a fool.'

'Perhaps you misheard Daddy.'

'I was there,' said Billy, joining in the conversation. 'He actually said that Miss Jenkins was a bloody fool. It was when she told him not to leave our car in the headmaster's car space.'

'It was a Saturday,' said Sally in defence of her father.

'That's quite enough,' said Fiona sharply. 'Let's start the maths homework.'

There was a knock and then Tessa looked round the door. 'Yes?' said Fiona.

'I wondered if the children would like to go to the stables.'

'They must do their homework.'

'There's a foal: born last week… just for hah an hour, Fi.'

'They have a test on Monday,' said Fiona.

'Leave them with me, Fi. I'll see they do their homework. Go for that long walk to Ringstone, you are always saying you enjoy that.' Tessa was keen to be rid of her: she loved to be with the children and they seemed to respond to her. Tessa was a born rebel and they sensed it and were intrigued.

Fiona looked at them. 'Very well. Thirty minutes and then you must do your homework.' She turned. 'I'm relying on you, Tess.'

There was a happy chorus as they declared their intention to work hard under their aunt's direction. Sally came round and squeezed her mother's hand as if asserting her love. Billy wasted no time before getting into raincoat and scarf. As Tessa took the children off, Fiona heard Billy telling her, 'If the Russians restore the monarch, he will have to be a commie Tsar.' It was his favourite joke since Silas had laughed at it.

Tessa was right, Fiona needed a little time to herself. There was so much to think about. She found an old raincoat and a man's hat in the hall and, wearing the walking shoes she kept in the back of her beloved red Porsche, she slipped away. Alone, striding through the misty rain, she made for the summit of Ringstone Hill above Singlebury. It was about six miles and she walked with the brisk determination with which she did so many other things.

She knew the way, she had done it many times, sometimes with the family and sometimes just with Bernard. She was gratified by the sight of accustomed gates, streams and hedgerows, as familiar as the faces of old friends: varying sometimes with fresh patches of soft mud, a shiny new brass padlock, or the rusting frame of an abandoned bike. The boundary of Whitelands was marked by six fallen firs, casualties of the winter gales. Shallow-rooted trees, like their human counterparts, were always the first to go. She looked at one. From its rotting bark came primroses uncurling their canary heads. She counted their petals as she had when a child: five petals, six petals, some with eight petals. All different; like people. She'd grown up believing that four-petalled primroses were lucky: no four-petalled ones in sight today. It was Bernard who explained that four-petalled primroses were a necessity of cross-fertilization: she wished he'd not told her. She strode on and waded through a vast rippling lake of bluebells before starting to climb again. No surprises; just the expectation before each grand view.

The light changed constantly. The wet fields became ever more radiant under the drizzling dark grey sky and the bright yellow gorse left its scent on the air. She scrambled up to the bare hilltop – for the stone is a stone in name only – and stopped to catch her breath. She'd not been aware of the wind but now it sent the light rain to sting her face, and crooned gently through the wire fence. She turned slowly to survey the whole horizon. Her kingdom: three hundred and sixty degrees and not a person, nor even a house in sight, just the distant clamour of a rookery settling down for the night. To the north the sky was buttressed by black columns of heavy rain. The exertion of the climb had driven from her mind all thoughts of what disturbing conclusions tomorrow's dialogue with Silas Gaunt might bring. But now her mind raced forward again.