‘My name is Annabel Grey.’ The woman was young, certainly younger than Markham, Sandy thought. But then Markham had taken a fancy to Evie Watt when she was only just out of school. Perhaps he liked his women that way. She seemed to take a breath before continuing. ‘I’m a student. Final year in Oxford. St Hilda’s. I’ve been away, out of contact, and I’ve only just seen the news. The Shetland murders.’

He wondered where she’d been. She made it sound as if she’d been travelling to far-flung and exotic places. Or to outer space. Cartoon images of spaceships and little green men floated into his mind.

‘I was Jerry’s girlfriend,’ she said suddenly, dragging him back to the matter in hand. It sounded more like a statement from a politician – a mission statement – than a declaration of love. ‘We were going to be married.’ There was a sudden silence, as if she thought there was nothing else to say.

‘When did you last hear from Jerry?’ Sandy asked. He was always happier with facts: dates, times, places. And it must have been the right note to take, because Willow smiled and gave him the thumbs up. Anyone else might have felt patronized by the obvious gesture of support, but Sandy was just relieved that he wasn’t messing up.

‘I spoke to him on the telephone the day before he went north,’ the woman said. There was a clarity in her voice that made Sandy wonder if she was a singer. It was hard to tell what she made of Jerry’s death. It didn’t sound as if she’d been crying, but perhaps she’d made the effort to put on a brave show. ‘After that, as I said, I was away for a few days and he couldn’t get hold of me. But he sent me a postcard. It arrived this morning.’

‘Could you describe the postcard?’ Again Willow beamed at Sandy, like a nursery teacher encouraging a particularly stupid child.

‘It was a reproduction of a painting,’ Annabel said. ‘Three musicians.’ So, Sandy thought, the card was identical to the ones they’d found in Jerry’s briefcase. He must have picked them all up from the Bonhoga at the same time.

‘And what did it say?’

For the first time the woman seemed uneasy, less than confident. ‘Look, this isn’t really something I feel comfortable discussing on the telephone. I’m coming up anyway. I’ll bring the postcard then. I need to see where Jerry died. I need to meet his family.’

‘Do the Markhams know about you?’

Another pause. This time so long that Sandy thought he should repeat the question.

‘I’m not sure,’ she said at last. ‘Jerry was going to tell them, I think, but he said he needed to wait for the right moment. Perhaps he hadn’t had the chance.’