The book of the famous Soviet illegal intelligence officer V.S. Grazhul tells about the history of Russian intelligence in the era of Peter I and Catherine II. Young intelligence officers studied on his research for many years. The book by V.S. Grazhul vividly shows the role of diplomatic intelligence in solving Russia's foreign policy problems. A galaxy of brilliant scouts and diplomats of the 18th century passes before the reader. The author reveals ethnic, territorial problems that later became the basis of large and tragic cataclysms of the Soviet Union and Russia.