1 ‘M. explained that this’: Liddell Diaries, 21 May, 1940, KV 4/186.
2 ‘M explained to him’: Ibid.
3 ‘considerably shaken’: Ibid.
4 ‘our policy with regard to’: Liddell Diaries, 12 June, 1940, KV 4/186.
5 ‘It seems that the Prime Minister’: Guy Liddell quoted in Hinsley and Simkins, British Intelligence in the Second World War, 52.
6 ‘mortified’ by the extent: Hugh Trevor-Roper, The Secret World (London: I. B. Tauris, 2014), 133.
7 ‘great contact’: Ex-MI5 officer quoted in Masters, Man Who Was M, 162.
8 ‘I’d like to impress on you’: KV 2/1221/44a.