The one name that is historically true is the Earl of Dumfries’ title, and his seat is indeed Dumfries House in Ayrshire. It was also the case that MacLeod of MacLeod sold the archipelago to the Earl of Dumfries in 1931, the year after the evacuation. The earl was a very keen ornithologist, and it was he who preserved it as a marine bird sanctuary and later bequeathed the land to National Trust for Scotland. However, in real life the earl was younger than my fictious version, and in 1930 his children were babies. I have used the framework of the earl’s interest and later ownership of St Kilda as a foundation for this story, but none of the events or characters you read within these pages are rooted in truth, only imagination.

Interestingly, Dumfries House passed out of the family’s ownership years ago, but the estate and buildings were rescued by Prince Charles in 2007 and saved for the nation. Having visited it myself, I would urge you to take the tour if you are ever in the area. It boasts the largest private ownership of Chippendale furniture in the world and we had afternoon tea in the old stable block! Homemade cakes and good tea followed by a wander around the maze.

I studied historic architects’ plans to manoeuvre Effie around the house in Part Two, so you really are walking through the corridors with her. However, there is one deviation from the truth here – in real life the ha-ha is situated on the north side of the house, but for logistical dramatic purposes I had to put it on the south side.

This has been a labour of love for me and it has been such a privilege to immerse myself in the history of St Kilda. When I returned from visiting it, I felt as if I’d been to the Galapagos or the Antarctic – it really is that special and rare and remote, so I’d like to thank my publishers, Pan Macmillan, for being so wholeheartedly behind the idea for this series. In spite of my draw to the place, I was nonetheless hesitant about setting the action in a faraway place, a hundred years ago, with no communications, no shops, no nightlife . . . But my editor, Gillian Green, and publisher, Lucy Hale, immediately saw that the lack of external stimulus would mean the story was driven by a cast of strong, vividly drawn characters instead. And on an island with no trees and only thirty-six inhabitants, those characters would have to work very hard and be quite ingenious if they wanted to keep any secrets – because of course they had them!

Everyone on the team has worked so hard to whittle, shape, sell, market, define and refine this book and I sincerely thank you all. I’m so proud of what we’ve achieved.