Bodyguard of Lies Bodyguard of Lies is a 1975 non - fiction book written by Anthony Cave Brown , his first major historical work . Named for a wartime quote of Winston Churchill , it is a narrative account of Allied military deception operations during the Second World War . The British and American governments resisted Brown ' s attempts to research the book . Many of the topics were still classified and he was denied access to British war records . The material in the book is predominantly based on oral testimony as well as some American records , declassified toward the end of Brown ' s research . Critical reception has been mixed , but generally negative . Contemporary historians , such as Charles B . MacDonald , praised the work – although some did comment on its length . Modern reviewers have identified inconsistencies or errors in the material , based on later declassified records . Also , some of Brown ' s personal conclusions have been questioned . Background . " Bodyguard of Lies " was Brown ' s first published book , following his career as a journalist in the United Kingdom and Australia . The work narrates Allied deception strategy on the Western Front for the years of 1943 and 1944 . It particularly focuses on Operation Bodyguard , both the operation and the book ' s title were inspired by one of Winston Churchill ' s war - time epigram s ; " In war - time , truth is so precious that she should always be attended by a bodyguard of lies . " Brown began researching and writing " Bodyguard of Lies " in 1961 . Most of the material is based on oral testimony from Second World War intelligence personnel , as well as records from the National Archives and declassified American records ( although Brown says that most of the book was written before he was able to access the latter , in 1974 ) . Brown wrote " Bodyguard of Lies " at a time when details of both cryptography and deception during the war were still classified . His attempts at research was resisted by the British and American governments ; he was denied access to British war records and had to undertake considerable work to obtain US records via Freedom of Information requests . Synopsis . " Bodyguard of Lies " opens with an introduction to Ultra , the codename for decrypted signals intelligence . It goes on to document the origins of the London Controlling Section ( LCS ) and the work of Dudley Clarke in the Middle East . In late 1942 , Allied high command in London became aware of Clarke ' s successes during the North African Campaign . Based on his theories of deception , the LCS was created under Colonel John Bevan and granted broad powers to plan deception strategy . The introduction finishes with a discussion of how the Allies evolved deception strategy prior to 1943 , including the Double - Cross System ( the Allied system of double agents ) . The second section of the book introduces the German intelligence forces , in particular Admiral Canaris and his " Abwehr " intelligence agency . Brown discusses early deceptions , such as those surrounding Operation Torch , conducted against the Germans , and how the Abwehr struggled to decipher the information it was being fed . The third section of the book covers Allied deceptions during 1943 , in particular Operation Mincemeat . Brown introduces Plan Jael , the early revision of Operation Bodyguard , and follows Bevan ' s work in creating the deception plan . The fourth section covers the events of early 1944 , leading up to the Normandy landings on 6 June . In particular , Brown discusses Operation Fortitude and the fictional First US Army Group , a key part of Bodyguard , calling it " the greatest charade in history " . The final section of the book covers events on and after D - Day , including physical deceptions carried out on the night of the invasion , and the continued impact of Bodyguard in the months after the landings . Critical reception . The book received mixed reviews ; particularly with regards to Brown ' s focus on minutiae , which received both positive and negative comment . Later reviewers also criticised the factual basis of the work – describing it as containing " a multitude of errors of detail " – with some reviewers rejecting Brown ' s analysis . One such error that Brown relates was a then - widely held theory that Churchill had known of German intentions to bomb Coventry in November 1940 , but that the British leader had hidden the information to avoid giving up the secrets of Ultra ( intercepted German communications ) . By 1976 , declassified records showed that the intelligence was in fact more vague than popular myth had suggested . Writing in 1996 , reviewer Russell J . Bowen ascribes this to Brown ' s reliance on secondary sourcing and oral interviews ( describing the book as an " outstanding example of scholarly investigative journalism applied to the field of oral military history " ) . Hugh Trevor - Roper , writing for " The New York Review of Books " , was highly critical of the " encyclopedic " detail in Brown ' s writing : " He piles on the illustrative ( or irrelevant ) detail . He cannot leave anything out . Every person mentioned must have a potted biography . Every place must be equipped with atmosphere , furniture , associations . " Roper also criticised the material , writing that Brown had inserted " a novel thesis " , that Allied deception during the war was controlled by MI6 , " which , in my opinion , is quite wrong . " Some critiques of the book have been positive . A 1976 " New Scientist " review praised the level of detail , saying that it " would ensure a large sale " . In a letter to the editor in reply , Deputy Chief Historian for the United States Army , Charles B . MacDonald , referred to the book as " the most important work on World War II in a quarter of a century . " Writing in " Military Review " , Alexander Cochran noted that the book was one of the first non - memoir accounts of intelligence operations during the war and was unusual ( for its genre ) in documenting sources . However , he went on to call the book " suggestive more than definitive " . Russell J . Bowen concludes that although the writing and coverage were better than similar books then available , " Cave Brown ' s work fails to escape the common stigma of intelligence narratives : considerable inaccuracy as to detail and occasional lack of validity of interpretation . "