Hattie, who had been given to obsession since she was a child, found herself haunted by the place. In her imagination she lived there, in fifteenth-century Shetland, when the islands were still culturally closer to Norway than to Scotland and Whalsay’s loyalties were to the other Hanseatic ports, to Lubeck and Hamburg rather than Edinburgh or London. She saw the sailing ships arriving into Symbister and her husband, the merchant, counting out gold coins to pay his men for the goods he was importing from Europe, and the money he was paying the islanders for their salt fish and dried mutton. In her daydreams it was spring, but the sun was shining and the island was green.

Did the skull Evelyn had found belong to the merchant or to his wife? They were starting to find more bones in the second trench and perhaps they already had enough evidence to know. There were times in the early morning, as the damp penetrated her body, when she thought the dreams were driving her mad. And it’s not just me, she thought. The dig’s getting to Mima too. Their last conversation had been pretty weird.

At seven o’clock she began to get dressed, still sitting in her sleeping bag, pulling on the layers of clothes she would need to stay comfortable during the day. On top of the T-shirts she wore the hand-knitted sweater Evelyn had made for her birthday.

The Bod was one of a string of bothies spread across the islands, places for backpackers to stay. This was an old croft house and it just contained four beds, a table and a camping stove. There was a shelf with some pans, cutlery and crockery, an open peat fire. The Bod had one cold tap and they had baths and washed their clothes at Mima’s house, or more often at Evelyn’s. Evelyn was almost as passionate about the project as Hattie, and often invited them to Utra for dinner. She mothered them. Hattie thought she had her eye on Sophie as a potential daughter-in-law. Sophie was easygoing and pleasant, she ate everything Evelyn put in front of her and she laughed at Sandy’s jokes. Hattie knew Sophie would never marry Sandy – she had wealthy parents and ambitions of her own, which didn’t include being a policeman’s wife in Lerwick – but she might have sex with him for her own amusement. That was the way Sophie was.