Richard Sorge was a spy, a Russian spy and an extraordinarily successful one. Two quotes illustrate this. The first is by Larry Collins, ''Richard Sorge''s brilliant espionage work saved Stalin and the Soviet Union from defeat in the fall of 1941, probably prevented a Nazi victory in World War Two and thereby assured the dimensions of the world we live in today.'' The second is by Frederick Forsyth, ''The spies in history who can say from their graves, the information I supplied to my masters, for better or worse, altered the history of our planet, can be counted on the fingers of one hand. Richard Sorge was in that group.''

Masquerading as a Nazi journalist, Richard Sorge worked undetected as head of a Red Army spy ring until he was arrested and executed in Japan during the Second World War. Such an astonishing story as Sorge''s is bound to attract attention but not only was this the first book to offer an authoritative account, it has, in many ways, not least in the quality of its writing, never been superseded. The authors rejected legend and found facts that were even stranger. They provide an account as reliable as it is enthralling of possibly the most successful spy who ever operated; a man who for eight years transmitted from Japan a continuous stream of the most valuable information, often derived from the highest quarters, culminating in precise advance information of Hitler''s invasion of Russia, of Japan''s decision not to attack Russia in 1941, and of the near certainty of war against America that October or November instead.

Jointly written books sometimes jar, but not this one. The authors had complementary skills, F. W. Deakin being an authority on twentieth-century European history and G. R Storry no less of an authority on twentieth-century Japan. Together they do justice to ''the man whom I regard as the most formidable spy in history,'' (Ian Fleming).