This book is well worth reading if only for the chapters on the Great Illegals; Blunt and Burgess; The Vegetarian (John Cairncross); Atom Secrets; and the Philby Reports--excerpts from the KGB files. Many of the last present hard intelligence. However, Philby's detailed account of wild goings-on in London clubs (including The Nuthouse) and their frequenters (including Happy Harbottle, Snooty Parker, and Buffles Milbanke) could well have been a colossal joke at the expense of the KGB, which was always pestering the spy to answer the same tiresome questions over and over. West's chapters on the early history of the Soviet Secret Service, which seem well documented, may be more of interest to the scholar than to the lay person. But I must say that I found the book absorbing as a whole.