‘At first he was quite polite,’ she said. ‘He apologized for disturbing me so early. Then he changed. As if a switch had been tripped. He began to rant. About how I’d ruined his daughter’s life. It wasn’t the affair with John that he objected to, but that I’d let Markham find out about it. “Would it have hurt you to be discreet?” As if I’d been boasting about the relationship to everyone I met. Then he said I’d turned him into a killer. Until that point I hadn’t believed that he was more than a strange middle-aged man.’ She looked up at Perez. ‘I reached for the phone, but he was too quick for me. And very strong. I suppose it’s hard physical work, building the yoals.’ She reached out towards her cup, but paused, her hand resting on the table. ‘How could someone who creates such beautiful objects turn into a monster?’

‘He wanted to protect his daughter,’ Perez said. ‘At least that was how it started. And he was convinced he was right, that in some sense the murder of Markham was justified. In his eyes, Markham was an evil man.’

‘But he couldn’t have thought that about John,’ Rhona Laing said. ‘Nobody could believe that John was anything other than kind and generous.’

Perez thought about that. It seemed to him that Watt’s instinct for survival had taken over then. He hadn’t been thinking about Evie when he killed John Henderson. He’d been protecting himself. At the same time hating himself for doing it. And that was why he’d attacked the Fiscal: he’d needed somebody else to blame.

Rhona was continuing her story. ‘He wrapped me in a piece of tarpaulin and stuck me in a van, drove me down to the marina. Nobody was around. Besides, nobody notices a scruffy white van. I did struggle when he took me out, Jimmy, but he was too strong.’ She sounded ashamed. ‘He lifted me as if I was a baby, put me below in the Marie-Louise and sailed her round to Hvidahus. A long sail. I know that now, but I didn’t at the time. I thought he intended to drown me then, out in the voe.’

She sat for a moment in silence. In the distance there was the sound of a curlew on the hill. ‘He knocked me around a bit in the cabin and I must have fainted. I don’t remember the trip to Hvidahus at all.’

Perez had been shocked by the marks on her arms, the bruised cheekbone, but hadn’t mentioned them. Rhona Laing wouldn’t be a woman to want sympathy. ‘When I woke up we’d arrived at Hvidahus pier. He made me walk to the hatchery. He had a knife to my back.’