Like Kipling's hero of the same name, Kim Philby was a man ""with two separate sides to his head""--half of which was working for England's Secret Intelligence Service, the other half for Russia for over thirty years in what must be certainly the most high handed chapters of the Great Game. He was also the Third Man, unidentified for years while suspected by M.I. 5 (and protected by Macmillan and the above SIS) who tipped off Burgess and Maclean. This tripartite collaboration by three writers of the Sunday Times (based on the exhaustive research of a twenty man team) is also the tripartite story of Philby, Burgess and Maclean who knew each other at Cambridge where they were first imbued with the Marxian mystique. But it was just this select background which, as Le Carre points out in his introduction, protected him as an ""upper class enemy of our blood who hunted with our pack."" . . . The Philby Conspiracy is not only one of the notorious gaffes of our time, but authors Page, Knightley and Leitch have converted, it into one of the genuinely sobering and fascinating narratives of livewire deception and defection.