She could hear the same sound now. Sophie’s sleeping bag wasn’t as good as hers but the cold never woke her. Hattie flicked on her torch. Six o’clock. Still dark outside and still misty. She could hear the regular moan of a foghorn far in the distance. Since they’d returned to the dig at Lindby, it seemed to her that Whalsay had become her entire universe. It was as if the fog cut the island off from the rest of the world. Her mother was a politician, a junior minister, and growing up Hattie had been surrounded by discussion of current affairs. The latest policy on healthcare, education, overseas aid, had governed their daily lives. Here she rarely read a newspaper, only saw television if it was on at Mima’s house or in Utra where Evelyn lived. World affairs had no relevance to her here. Digging away the layers of soil from the buried house at Lindby, she found herself engrossed in political concerns – the decline of the Hansa, the emergence of wealthy men in Shetland – but ones that had nothing to do with the present.

Sophie thought Hattie was driven on by ambition, and it was true that at one time the only future she saw for herself was as an academic. That meant a good PhD and a reputation as a solid and intelligent archaeologist. Now another, more personal obsession had taken over. She wanted to stay in Shetland.

The site had been a merchant’s house, much grander than she’d first thought. Whalsay had been an important port in the Hanseatic League – the medieval trading community of towns along the Baltic and the North Sea coasts – and she’d assumed that the owner had been a trader. But there were no records, no name for the owner. The university had been working in Shetland for years and Hattie had come first as an undergraduate, working on the dig at Scatness. She’d come across the site at Setter by chance and had found herself tantalized by the mystery. How could such a substantial house have disappeared so completely from Shetland’s history? It didn’t show up in any of the early maps or the records. She hoped the dig might provide an answer. Paul, her supervisor, had first thought that there might have been a fire to wipe away traces of the dwelling, but they’d found no evidence of that.