Now and again readers ask how long it takes me to research and write a book. I ballpark it at three years, depending on the availability of sources and narrative complexity. That amount of time sounds right to some folks, quick to others. The truth is, however, each of my books would have taken many more years if not for the community of people who contribute to the finished work. And the quality would have been far, far diminished without them.
First, I would like to applaud my research assistants who spearheaded my efforts in Norway (Windy Kester and Arne Holsen) and Germany (Almut Schoenfeld). They were tireless in helping me comb through archives and in tracking down individuals to interview.
Before I began my research, all but one of the saboteurs (Joachim Rønneberg) had passed away. I had the benefit of their recollections in numerous interviews, memoirs, and diaries, but even this bounty did not provide the kind of rich portrait I hoped to paint of each of them. Fortunately, their families offered to speak with me, sharing family lore as well as a number of documents that have never before been seen. A big thanks to the Haukelids (Kirvil, Bjørgulf, and Knut), Skinnarlands (Marielle, Kirvil, Ron, Inger-Berit Bakke), Hauglands (Trond, Torfinn, Torill), Poulssons (Unni, Mia), Tronstads (Leif Jr., Sidsel), and Finn Sørlie. In particular, I’d like to send my appreciation to Leif Tronstad Jr., who shared many, many hours of his time and family papers with me, as well as reading the final draft of the book. Also to Marielle Skinnarland for her generous attention to my exhaustive list of questions. And to the Hauglands, who put me up in their cabin outside Vemork and took me on a cross-country ski tour of the area (and even offered some of their father’s gear for me to use). I also appreciate the insight of former Kompani Linge member Ragnar Ulstein and a handful of Norwegians who know this story well and provided much guidance to me, including Bjørn Iversen, Svein Vetle Trae, Berit Nøkleby, Asgeir Ueland, and Tor Nicolaysen. In particular, Svein Vetle offered me a wonderful weekend at his cabin, not to mention the maps for this book.
A work of history is often only as good as the primary sources available to the author. In this case, they were plentiful and rich. One of these was the Norges Hjemmefrontmuseum (NHM). It is a gem of an archive, and its staff are first-rate experts on the Norwegian homefront resistance. My appreciation to my guides there: Frode Faerøy, Ivar Kragland, Benjamin Geissert, and Arfinn Moland (who provided me with an unpublished interview with Gunnerside leader Rønneberg that ran over a hundred pages of pure gold). Rjukan’s Norsk Industriarbeidermuseum (VM) also held great treasure, and I would have been lost without its director, Kjetil Djuve, and Ingelinn Kårvand. Also a big thanks to the staffs at the National Archives (UK) who fielded innumerable requests on my behalf, as well as those at the Imperial War Museum, Niels Bohr Library, and Rensselaer Institute, among others. Without my translators, Carl Stoll and Mark McNaught, much of this material would have been indecipherable.
Once the research is done — and the first draft complete, another community comes to my side. A shoutout to my early readers, Carl Bartoli, Henry Bartoli, John Tuohy, and Mike Faley, who clarified atomic physics as well as the intricacies of B-17 bombing runs. As always, my first-line editor, Liz O’Donnell of the Little Red Pen, shaped and shifted and refined almost every paragraph in the book. I can never sing her praises enough. Thanks to my literary agent — and consigliere in all things publishing — Eric Lupfer at William Morris Endeavor, and his colleagues Ashley Fox, Simon Trewin, and Raffaella De Angelis. Eric brought me home to my longtime publisher Houghton Mifflin Harcourt and my superb editor there, Susan Canavan. She’s a great champion for my work — and a friend. Kudos also to the always wonderful Megan Wilson, the marketing wizard Carla Gray, Jenny Xu, and Melissa Dobson.
And finally, thanks to Diane and our precious girls Charlotte and Julia, who live through the ups, downs, and in-betweens of the life of an author. You make it all worth it.