They spent hours poring through the maze of streets and alleys that was old L‘Escala. Most of the businesses and shops were still open, reminding visitors that this was a working town first, a resort second.

Their week passed too quickly, as they relaxed in each other’s company. Soon it was New Year’s Eve. In common, it seemed, with much of L‘Escala, they had made a reservation in their special restaurant in St Marti, where a gala supper was advertised to see out what had been for them a momentous year.

As usual, the food was superb. A feast of calcots, the unique Catalan vegetable, was followed by thick, creamy tomato soup, before the arrival of the main course: a spectacular baked fish-pot. The meal drew to its leisurely conclusion before midnight.

Suddenly Skinner took an envelope from his pocket and handed it to Sarah.

Puzzled, she tore it open. Inside was a pale blue card, with a gold question-mark on the front. She opened it. Inside there was a second question mark, in Bob’s scawled style.

She looked up at him, and as she did so, he placed a small box before her on the table. Embossed on the lid, in gold leaf, was ‘Hamilton & Inches, Edinburgh’. She lifted the lid and a large single diamond set on gold sparkled out at her.

‘Well,’ said Bob, in a voice she had never heard before, ‘are you daft enough to marry a copper with very limited promotion prospects?’

‘My love,’ she answered, twin tears tracking down her cheeks, above her shining smile, ‘I’d be daft not to!’

Bob took the ring from the box and slipped it on to the third finger of her left hand. It was, of course, a perfect fit.

As Sarah stared at the diamond on her finger, parties at the three surrounding tables, who had been watching breathlessly, broke into applause. A dark Spanish man came over, smiling, and shook Bob’s hand. His wife embraced Sarah. And just at that moment, midnight began to strike.

Bob reached across the table and took both of Sarah’s hands in his. ‘Happy New Year, my darling. You know, since Alex was born, this is the first one I haven’t brought in with her. Once, even, I was on duty, in the office, and I took her in with me. But things change and lives move on. Now I don’t intend ever to bring in another without you by my side.’

Normally, Bob danced only under extreme duress. But that night, as he and Sarah drifted around the floor to the music of the small band, it was as if they were waltzing on air, above the stone floor of the terrace restaurant.

At 1.00 a.m. local time they used the pay-phone in the corner to call Alex. To their surprise they connected first time. The background noise confirmed that it was midnight in Scotland, the sacred hour of ‘The Bells’, and that Alex had a full house.

‘Happy New Year, love,’ Bob shouted into the telephone.

She bubbled down the line. ‘Happy New Year, Pops! Are you having a terrific time?’

‘Yes, pretty terrific.

‘Listen, baby, hold on to a chair for a minute, we’ve got something to tell you. You’re going to have a stepmother!’

Twelve hundred miles away, Alex said, ‘Yeah, wonderful. About time, too. Put Sarah on. Oh, look at me, I’m crying.’

Sarah took the telephone from Bob. She tried to imagine what a stepmother tone should sound like.

‘Right, my girl. Are you behaving yourself?’

‘Of course not, are you? Sarah, that’s wonderful. Did he manage to propose without making it sound like he was charging you with something?’

‘Listen kid, your old man’s got style. It was wonderful. Right on the stroke of midnight he pops the question. When we get home I’ll tell you all about it.’

The cut-off noise began to sound.

‘Have a great time. See you soon!’

Sarah replaced the receiver and turned to Bob. She threw her arms around his neck and kissed him.

‘You’ve no idea how good it feels to be official.’

‘Oh yes, I have. You’d better start planning. Your track record shows that you’re not very good at being engaged, so I don’t intend for this to be a long one.’

Sarah took him at his word. As the taxi wound past the jetty where the Olympic flame had landed in 1992, and along the dark beach road to L’Escala, their plans took shape. It would be an Easter wedding, in Edinburgh. Alex would be maid of honour, Andy would be best man. If his uncertain health allowed him to travel, Sarah would be given away by her father, who had talked of a trip to Scotland when she had visited her parents in Florida.

‘If he can’t come maybe Andy could do that too,’ she said.

‘Can he do both?’

‘Why not? Or maybe the Chief, what is it you call him, Proud Jimmy, maybe he could do it.’

‘Steady on. We’re not that chummy!’

When she could speak, Sarah whispered in his ear. ‘If that’s what being engaged does for you, I don’t know if I’ll survive marriage.’

‘Nnnn.’ Bob nuzzled his face into her neck, closed his eyes and, smiling, settled down to sleep.

He was still smiling next morning on the terrace, as they ate breakfast in the perfect sunshine. So was Sarah.

‘That was a pretty high standard we set ourselves last night, boy. Tell me, Assistant Chief Constable Skinner, do you get as intense as that when you’re working on your cases?’

He nodded at the recollection. And then it was as if his face had been flooded with light.

He seized her shoulders in each of his lean hands and kissed her, taking her by surprise and astonishing the English emigré neighbour who happened to be walking past with his black labrador.

Dr Sarah Grace Skinner to be, you are a genius. That’s it! The word you used last night. The word coppers never use.

‘Cases!’