The boat that waited for them at Crovie’s pier was not the skiff she had seen that morning, but a larger boat clearly made for fishing. It was about six metres long with an open cabin over the steering wheel and an enclosed prow. It was navy blue and white and on its side, painted in red and gold, was its name: Cassie’s Joy.

Less than five minutes later and for the second time that day, Anna found herself speeding over the waves, the coastal cliffs rearing into the cloud-specked sky.

‘We’re not going far,’ Robert said, once they’d taken a long, wide curve out of the bay and left Crovie behind. ‘There’s a cove out towards Rosehearty, beyond Pennan, that’s usually full of them. Have you ever harvested razor clams before?’

‘No,’ Anna shouted back, over the sound of the outboard motor and the ubiquitous roar of the wind. ‘I’ve cooked with them, but that’s it.’

He nodded. ‘It takes some muscle.’

‘And some salt.’

Robert looked over at her, surprised. ‘You do know a bit about it, then.’

‘I know the theory of many things,’ she said, ‘but the reality of very few.’

He smiled, the first such expression she’d seen on his face since he’d knocked at her door. ‘Sounds familiar,’ he said.

The hop around the headland was brief. The cliff here was another monolith of sheer rock, reaching skyward in ragged clefts. Anna noted that there had been landslides here, too – signs that she was beginning to learn. They looked like shallow channels in the rock and mud, almost like streambeds run dry.

Robert tied off the boat, though there was still a foot or so between the Cassie’s Joy and the beach, and Anna could see why he’d recommended wellington boots.

‘Right. Grab that,’ he said, pointing to a galvanized bucket near her feet. ‘The salt’s in the box inside. Bucket, salt, and over the side. Okay?’

In the next moment, he had hopped into the water, holding out a hand for the bucket. She passed it to him and then clambered inelegantly into the cold North Sea. The water splashed up to her knees, soaking the walking trousers she was still wearing from her earlier walk.

She waded after Robert, who had reached the shore and turned to wait for her. He waved at the wet sand beneath their feet.

‘Just a few here to choose from.’

In ridges of sand left by the outgoing tide were hundreds of holes. Some had piles of ejected sand beside them, but others – small circular indentations that disappeared beneath the shallow film of brine caught by the motion of the tide – were clear, denoting the hidden clam’s air holes.

‘There are so many!’

Robert nodded. ‘I’ll pour, you catch.’