I owe a tremendous amount to many people.
Most of all, I thank the extended Fuchs family, the patriarch of which is “young” Klaus, who is now all grown up and who sat for many, many interviews with me, and his wife, Sabine, who was a gracious hostess for my multiple visits. His son Gerhard was instrumental in my acquiring court records from the 1930s and documents at the Bundesarchiv as well as passing on family lore. Heidi and Marianna Holzer answered all my questions about their mother, Christel Fuchs, as did Steve Heinemann. Fuchs’s cousins Silke and Dietmar Göbel shared family genealogy and photographs.
Without their collected memories and mementos Klaus’s story would have lacked the understanding that Alan Moorehead tried to find from Max Born almost seventy years ago.
Another family intimately involved is that of Max Born, whose children and niece and nephew knew Klaus Fuchs. Many of them we have lost: his son, Gustav, and wife, Faith, daughter Irene Newton-John, niece Renata Koenigsberger, and nephew Ralph “Rolli” Elliott. His grandchildren who had heard the stories have been extremely supportive, with granddaughter Carey and husband Darren reading chapters and offering advice and grandson Bash giving guidance. Both Walter Kellermann and Walter Ledermann worked with Born and played in the physics/math quartet in Edinburgh with Klaus. Walter Kellermann’s recollections of internment and his memoir were priceless. And then there are the Born cousins: Anita Pollard, Katie Fischel, and Sophia Kingshill who regularly entertained me, offered advice, and read some chapters too.
The same is true of friends, many of whom I made along this long path. The Buneman family (Peter, Michael, and Naomi) and their late mother, Lady Mary Buneman Flowers, who was a very lovely and lively lady—and her memoir—gave me a strong sense of Harwell and Klaus. Others who agreed to interviews, tours, meetings, teas, and lunches and in every way were supportive are Brian Pollard (Bristol), Kathy Behrens Cowell (Derek Behrens), Charles Perrin and Nicola Perrin (Sir Michael Perrin), Thomas Giesa, Wolfgang Gleiser, and Peter Schütz (Martin Luther Gymnasium, Eisenach), Patricia Shaffer (Los Alamos), Lili Hornig (Los Alamos), Stewart Purvis (the Free German League of Culture), Jo Peierls Hookway (the Peierlses), Nigel West (MI5), Mike Rossiter (Klaus Fuchs), Alexander Vassiliev (the KGB), Victor Ross (internment), Günther Flach (the ZfK, Dresden), Henry Richardson (ethics), Derek Leebaert (the cold war).
And then there were those who read most or some of the manuscript: Bill Leahy, always checking in with me and keeping me moving, reading and critiquing everything I gave him, and his wife and my college friend, Chris, too; Robby Brewer, who also read everything and weighed in with a good critical eye; Margaret Ayres and Steve Case, who gamely suffered through some bad chapters early; Kathryn Johnson, who advised on creating a stronger narrative style; Richard Squires, whose insightful critique of several chapters reformed my narrative; Joe Martin, and Cameron Reed, who bolstered the physics; Cristina Fischer, who critically reviewed the chapters on student unrest in Germany; Cindy Kelley, who, at the last minute, obliged my needs for review of the chapters on the Manhattan Project; Allen Hornblum, who reviewed background material on Harry Gold; John Earl Haynes, who introduced me to Venona; and Peter Collisson, Ed Mayberry, and John Korbel, who read the MI5 chapters early and gave me helpful feedback.
Without German friends to help with some of the translation, I’d still be struggling through the videos and some German archival material: Robert Metzke, Matthias Rolke, and Jan Ehrhardt. My skating coach Alexei Kiliakov tackled some Russian for me, and Caroline Danforth set her mind to a very difficult letter in Sütterlin.
A special thanks to everyone who offered a suggestion, or a reference, or entry to something or someone: Andrew Farrar, Dieter Hoffman, Alex Wellerstein, John Wilhelm, Michael Goodman, Tom Steiner, Andrew Robinson, Sabine Lee, Geoff Andrews, Steve Feller, and an extra special thanks to Kathryn Imboden, who rushed to the Swiss Alps to rescue copies of the Geheeb archives for me and who offered unending support along with Anne Wesp, both friends for more than fifty years.
The archivists at the thirty or so libraries and archives that I visited deserve a big thanks. They were always gracious and informative, often identifying files I wouldn’t have thought to look at, especially those for the University of Kiel at the archives in Schleswig.
Then there is the “team,” which began with Merloyd Lawrence introducing me to Carolyn Savarese, my agent at Kneerim & Williams—thank you, Merloyd—who made the connection to Wendy Wolf at Viking. They are both tough taskmasters when needed who cushioned the required rigor with support, kindness, and humor. The immeasurable and deft skills of Bill Patrick added the polish—and then some—at the end.
Terezia Cicel, Wendy’s assistant at Viking, answered technical questions quickly and knowledgeably and kept everything on schedule, and my friend Laura Cohen worked willingly and tirelessly on the endnotes. And the copy editor, Ingrid Sterner, saved me from so many mistakes.
Last, but certainly not least, are my three children—Elizabeth, Jake, and Sarah—who listened patiently to my problem of the day with love and caring. The smiles and hugs from my two granddaughters kept the joys of life in mind for me.