‘She was his wife?’ asked Aunt Frances, realizing she would be informed whether she wished it or not.

‘Yes. He loved her — oh, my goodness those two! She was very tall and as thin as a rake, with a big nose, and she had a stammer, but for him she was the whole world. It was very hard for him to leave Vienna because her grave is there. He’s old now, but it doesn’t help.’

‘Why should it?’ said Miss Somerville tartly. And in spite of herself: ‘How old?’

‘Sixty-four,’ said Ruth, and Miss Somerville frowned, for sixty-four is not old to a woman of sixty.

Ruth, working in the compost, looked up at the formidable lady and made a decision. You had to be worthy to hear the story of Mishak’s romance, but oddly this sharp-tempered spinster who had left Quin alone was worthy.

‘Would you like to hear how they met — Uncle Mishak and Marianne?’

‘I don’t mind, I suppose,’ said Aunt Frances, ‘as long as you go on with what you’re doing.’

‘Well, it was like this,’ said Ruth. ‘One day, oh, many, many years ago when the Kaiser was still on his throne, my Uncle Mishak went fishing in the Danube. Only on that particular day, he didn’t catch a fish, he caught a bottle.’

She paused to judge whether she had been right, whether Miss Somerville was worthy, and she had been.

‘Go on then,’ said the old lady.

‘It was a lemonade bottle,’ said Ruth, pushing back her hair and getting into her stride. ‘And inside it was a message…’

Late that night, Aunt Frances stood by her bedroom window and looked out at the sea. It had rained earlier, raindrops as big as daisies had hung on the trees, but now the sky was clear again, and the moon was full over the quiet water.

But the beauty of the view did little for Miss Somerville. She felt unsettled and confused. It was all to be so simple: Verena Plackett, so obviously suitable, would marry Quin, Bowmont would be saved and she, as she had intended all along, would move to the Old Vicarage in Bowmont village and live in peace with Martha and her dogs.

Instead, she found herself thinking of a woman she had never known, a plain girl standing terrified before a class of taunting children in an Austrian village years and years ago. ‘She was as thin as a rake,’ the girl in the garden had said, ‘with a big nose, and she had a stammer. But for him she was the whole world.’

Frances had been just twenty years old when she went to the house on the Scottish Border, believing that she had been chosen freely as a bride. She knew she was plain, but she thought her figure was good, and she was a Somerville — she believed that that counted. The house was beautiful, in a fold of the Tweedsmuir Hills. She had liked the young man; as she dressed for dinner that first night, she imagined her future: being a bride, a wife, a mother…

It was late when she returned to her room where Martha waited to help her to bed. She must have left the door open, for she could hear voices outside in the corridor.

‘Good God, Harry, you aren’t really going to marry that anteater?’ A young voice, drawling, mocking. A silly youth, a friend of her fiancé’s who’d been at dinner.

‘You’ll have to feed her on oats — did you see those teeth!’ A second voice, another friend.

‘She’s like a hacksaw; she’ll tear you to pieces!’

And then the voice of her young man — her fiancé — joining in the fun. ‘Don’t worry, I’ve got it all worked out. I’ll go to her room once a month in my fencing kit, that’s padding enough. Then as soon as she’s pregnant I’m off to town to get myself a whizzer!’

It was Martha who shut the door, Martha who helped her to undress. Martha who kept silence when, the next morning, Frances left the house and said nothing, enduring the anger of her parents, the puzzlement of the family on the Border. That had been forty years ago and nothing had happened since. No door had opened for Frances Somerville as it had opened for that other girl in an Austrian village. No black-suited figure with a briefcase had stood on the threshold and asked her name.

Irritated, troubled, Frances turned from the window, and at that moment Martha came in with her evening cocoa — and the puppy at her heels.

‘Now what?’ she said, relieved to have found something to be angry about. ‘I thought you were taking him down to The Black Bull after tea.’

‘Mrs Harper sent word she couldn’t have him,’ said Martha. ‘Her mother-in-law’s coming to live and she hates dogs.’ She looked down at the puppy who was winding himself round Miss Somerville’s legs like a pilgrim reaching Lourdes. ‘He’s a bit unsettled, not having been down with the students today.’

Frances said she could see that and picked him up. Nothing had improved: not his piebald stomach, not his conviction that he was deeply loved.

That was what things were coming to, she thought. Twenty years ago, the wife of a publican would have been honoured to have a dog from the big house. Any dog. It was all of a piece, this idiot mongrel… all of a piece with waitresses who wept over the autumn crocus, with cowmen who sang and Wagner’s stepdaughter with her unequal eyes. Comely slept in her kennel; she would not have dreamt of coming upstairs. And it wasn’t any good rereading Pride and Prejudice yet again. Mr Darcy might have been disappointed in Elizabeth Bennet in chapter three, but by chapter six he was praising her fine dark eyes.

‘I’ll take him down,’ said Martha, reaching for the dog.

‘Oh, leave him for a bit,’ said Frances wearily. Still holding the puppy in her arms, she sat down in the chair beside her bed.

‘I have come to fetch you,’ the little man had said, opening his briefcase, removing his hat…

It began so well, the trip to the Farnes. The weather had been unsettled for the past two days, but now the sun shone again and as the Peggoty chugged out of Sea-houses harbour, they felt that lift of the heart that comes to everyone who sails over a blue sea towards islands.

The puppy felt it too, that was clear. Its rejection by the innkeeper had left it emotionally unscarred and its position as student mascot was now established. Quin would not allow it in the dinghy, but the Peggoty was a sturdy fishing boat which he rented each year and there was a cabin of a sort where the owner stored his lobster pots and tackle — the dog could be shut in there when they landed.

Dr Felton had stayed behind to sort out the previous day’s samples; Quin was at the wheel, steering for one of the smaller islands where the warden was waiting to show them the work in progress. They had missed the spectacular breeding colonies of the spring when the cliffs were white with nesting guillemots and razorbills and the puffin burrows honeycombed the turf, but there were other visitors now: the migrant goldcrests and fieldfares and buntings — and the seals, hundreds of them, returning to have their pups.

They passed Longstone lighthouse and the Keeper, digging his vegetable patch, straightened himself to wave.

‘That’s where Grace Darling came from, isn’t it?’ asked Sam, thinking how like the Victorian heroine in the paintings Ruth looked with her wind-whipped hair.

Quin nodded. ‘The Harcar rocks are to the south, where the Forfarshire broke up. We’ll see them on the way back.’

‘It’s amazing that Mrs Ridley’s grandmother knew her, isn’t it?’ said Ruth. ‘Well, the family… someone in a legend. She said it wasn’t the tuberculosis so much that killed her, but the fuss they made of her afterwards making her a heroine. I wouldn’t mind being a heroine — it wouldn’t kill me!’

Quin didn’t doubt this. ‘How did you meet Mrs Ridley’s grandmother?’ he asked curiously. ‘She usually keeps herself to herself.’

‘I went to fetch some eggs and we got talking.’

They were very close to the shore when it happened. Dr Elke had gone into the cabin to hand out their belongings, Quin was watching the point, steering for the jetty on the far side.

And what did happen at first was simply funny. A large bull seal bobbed up unexpectedly not four feet from the boat on the island side. A benevolent, comical seal with long grey whiskers, making himself known.

The puppy had been asleep on a pile of canvas. Now he woke, lifted his head.

The seal sneezed.

The effect was electric. The puppy let out a sharp bark of excitement and clambered onto the gunwale. What he was seeing was unheard of… an ancestor? A monster? His barks became frenzied; he scrabbled with his feet against the wood.

The boat tilted.

It took only a second… one of those seconds that no one can believe are irreversible.

‘He’s gone! Oh God, the puppy’s gone!’

Quin looked round, assessed the creature’s chances. The sea was calm, but the tide here ran at five knots. To be dashed against the rocks or swept past them out to sea were the alternatives — yet he began to turn the boat, heading her into the wind.

No one dreamt that this was only the beginning. Ruth was impetuous, but she was not mad. Dr Elke was just emerging from the cabin, she was too far away to see; the others were leaning over the side, trying to chart the progress of the little dog as he bobbed up, paddling frantically, and vanished into the trough of a wave. Only when Pilly began to scream — then they saw. Saw Ruth’s bewildered face as the current took her, saw her head turn… not to search for the dog now… to measure her terrifying speed.

The next seconds were the stuff of Quin’s nightmare for years to come: those seconds in which he forced himself to remain where he was till he had turned the boat fully into the wind and shut down the engine. Not letting himself move till he could rely on the Peggoty to hold steady.