Berman sets out in this book to report on his interviews with just about all the leading members of the Saigon press corps during the Vietnam War to determine whether they had had any idea that Pham Xuan An had been a Vietcong spy. They all say that An had been a completely trusted associate. He was given U.S. government documents, including military war plans. He was present in the room when U.S. officials were discussing sensitive matters. An went about creating his cover by spending two years attending a California college to get a degree in journalism -- and to learn how to act and speak like a typical young American. He then returned to Saigon and began working as a journalist, becoming Time's chief reporter there. The press corps accepted him as "one of our loyal Vietnamese." Only with the fall of Saigon and the victory of the North did it come out that An, who died recently, had been a spy all those years. Berman, in recapturing the atmosphere of Saigon during the war, has also documented the extraordinary group of American correspondents who were stationed in Saigon to report on the war. The outstanding journalists who knew and trusted An included David Halberstam, Stanley Karnow, Frank McCulloch, Robert Shaplen, and Neil Sheehan. An was also a personal friend of William Colby and Lucien Conein of the CIA and Colonel Edward Lansdale, the leading American expert on irregular warfare.