As well as the files released into the public domain, I have family connections to Maclean that resonated and gave me an opportunity to look at and use material that otherwise would not have been available. One of my grandfathers was, like Maclean, a convinced Communist who held firm to his beliefs (at some personal cost) throughout his long life and believed to the end that his ideology would eventually prevail to create a more peaceful and equal world. My other grandfather, who features in the book, was a career diplomat who worked with Maclean on some of the West’s most closely guarded secrets, notably atom bomb policy in the terrifying early years of the Cold War; was his boss in his last posting in London; was as stunned as all his colleagues when he saw the evidence that the rising star was the traitor they had been hunting for years; and was the last official to see him on British soil. Both of these grandfathers’ private writings gave me valuable insight into Maclean.
Maclean’s brother Alan, who became a publisher when he was forced to leave the Foreign Office, was a family friend, which enabled me to see not only their sister’s unpublished memoirs, which give a radically different version of the weekend of his defection in particular; but also, just when the book was about to go to proof, access to a box of Alan’s papers stored in a library in Cambridge marked simply ‘Donald’ which contained a cache of private letters and, best of all, an extraordinary document written by Maclean in Moscow not long before his death in which he looked back at his career and his beliefs in a remarkably open and revealing way.