John le Carré is viewed by many critics as one of the best spy and espionage novel writers. His most famous works are The Spy Who Came in from the Cold; Tinker, Tailor, Soldier, Spy; and The Little Drummer Girl.     Peter Wolfe has produced an informative study of le Carré's works, showing how le Carré's five years in the Service (British Intelligence) helped him become a keen observer, social historian, and expert in bureaucratic politics. He has supplanted the technological flair marking much of today's spy fiction with moral complexity and psychological depth. He shows us what spies are like, how they feel about spying, and how spying affects their minds and hearts.