Set in 1959 in Europe and Africa during the days of the Cold War, it is narrated in the form of reports, overheard conversations, and various documents from a multitude of sources of different nationalities, supposedly giving the reader an authentic picture of what an actual intelligence operation might be like.

McCarry had previously been an undercover operative for the Central Intelligence Agency for nine years, and the book was hailed for its apparent authenticity and realistic depiction of tradecraft.

Like all of McCarry's books, this one displays "an almost Jamesian awareness of [its] European locale, the special authenticity of a loving expatriate writing of an adopted foreign land.

In future novels he becomes richly portrayed, with an elaborately detailed family life in pre-War Berlin that plays an important role in some of the books.

[7] While not all of this information is consistent with what we learn about him in later (and presumably more authoritative) books, it does not have to be: since Christopher is a professional agent used to dissembling, he does not have to tell the truth when he says he does not resemble his own brothers and sisters (if they exist), or in talking about other details of his past life.

[9]Writing in the Wall Street Journal in 2009, the noted contemporary thriller writer Alan Furst called it number two of the five best spy novels ever written: It is a travelogue that bristles with suspicion and deception—but don’t listen to me, listen to a certain highly acclaimed spy novelist who reviewed McCarry’s literary debut: "The level of reality it achieves is high indeed; it is superbly constructed, wholly convincing, and displays insights that are distinctly refreshing.

In the magisterial Twentieth Century Crime and Mystery Writers, George Grella called it "something of a masterpiece, a novel of espionage that succeeds at every ambitious level the author attempts and reverberates with possibility".

If McCarry continues to write as well in the future, he may turn out to be the American John le Carré; there is no higher praise a spy novelist can earn.

Variations such as Bram Stoker's famous vampire novel, Dracula, (1897) added other entries to the traditional letters: telegrams, diaries, newspaper clippings, and doctor's notes among others.

The mystery/thriller field has a long tradition of using the epistolary form, notable examples being Wilkie Collins's The Moonstone (1868) and Michael Innes's Lament for a Maker (1938).

As in most epistolary novels, an obvious weakness is the unlikelihood of such long reports and letters being penned in a few hours late at night in the midst of trying circumstance, always in a flawless literary narrative style.

The story itself, however, begins in Geneva, where a Polish historian, Tadeusz Miernik, works for the World Research Organization, an agency of the United Nations.

The most vivid character in the book is Kalash el Khatar, a tall, black, flamboyant, Oxford-educated Sudanese prince who considers all whites and their ways to be distinctly inferior.