There was quite a different perspective on the town from the water. A monochrome vision like a black-and-white film. She could see the backs of the buildings on Harbour Street. The women in the fisheries were getting ready for the lunchtime rush, carrying white plastic buckets of prepared potatoes from an outhouse at the end of the yard. The guest house looked rather grand from here, the narrow windows symmetrical and the grey stonework as solid as a fortress. There was a small garden between the house and the shore. Beyond, the tower of St Bartholomew’s dominated. She felt like a voyeur, a peeping Tom looking at the world from a hiding place. Though they were hiding in full sight.

‘Why did you lie to me, Malcolm?’ They were outside the harbour wall now and there was a slight swell on the water. She’d always been a good sailor and was untroubled by it. ‘You said you hadn’t had any contact with Margaret recently.’

‘I haven’t!’ But he sounded like one of the young scallies she used to round up as a junior PC, all bluster and swearing.

‘Come on, Malcolm man. You were seen dropping her off at the Haven the day before she died.’

He didn’t reply immediately and the only sound was the rasp of the engine and gulls screaming.

‘Look, man, talk to me. This is about as unofficial as it gets, in a bloody boat in the North Sea.’ With me looking like the Michelin man in a bright-orange life jacket.

‘We were friends,’ he said. ‘I was probably the only real friend she had round here.’

‘Lovers?’

He shook his head sadly. ‘A long time ago. Not recently. Not many times even then.’ He paused. They were halfway across the stretch of water that separated the island from Mardle. ‘And we didn’t meet much as friends when I was still married. She knew what I felt about her and thought she’d get in the way. She said that it wouldn’t be fair to Deborah. She was kind enough when I was getting divorced, but she made it clear there was no chance of us getting together again.’

‘Is that what you wanted?’ They were close enough to the island for Vera to make out details. The warden’s house and the muck on the cliffs where the seabirds had nested. She tried to remember more details of the trip she’d taken there with Hector to steal birds’ eggs all those years ago, but all that came back was the sense of foreboding and the dreadful certainty that they’d be caught. ‘You wanted more than friendship, even now?’

‘I adored her from the first time we met,’ Kerr said. ‘I should never have married. When I lay next to my wife I was dreaming of Margaret.’