Excerpt from 'A Spy Among Friends'

The word most consistently used to describe Kim Philby was "charm," that intoxicating, beguiling, and occasionally lethal English quality. Philby could inspire and convey affection with such ease that few ever noticed they were being charmed. Male and female, old and young, rich and poor, Kim enveloped them all. He looked out at the world with alert, gentle blue eyes from under an unruly forelock. His manners were exceptional: he was always the first to offer you a drink, to ask after your sick mother and remember your children's names. He loved to laugh, and he loved to drink -- and to listen, with deep sincerity and rapt curiosity. "He was the sort of man who won worshippers," said one contemporary. "You didn't just like him, admire him, agree with him; you worshipped him." A stutter, which came and went, added to his appeal, betraying an attractive glimmer of fragility. People waited on his words, for what his friend, the novelist Graham Greene, called his "halting stammered witticisms."

Kim Philby cut a dashing figure in wartime London. As the Times correspondent in the Spanish civil war, reporting from the rebel Nationalist side, he had narrowly cheated death in 1937 when a Republican shell landed near the car he was sitting in (eating chocolates and drinking brandy), killing all three of the other passengers. Philby escaped with a minor head wound and a reputation for "great pluck." General Franco himself had pinned a medal, the Red Cross of Military Merit, on the young war reporter. Philby had been one of only fifteen newspaper correspondents selected to join the British Expeditionary Force sent to France on the outbreak of the Second World War. From the continent he wrote wry, distinctive dispatches for the Times as he waited with the troops for the fighting to start: "Many express disappointment at the slow tempo of the overture to Armageddon. They expected danger, and they have found damp." Philby continued reporting as the Germans advanced and quit Amiens with the panzers already rumbling into the city. He took ship for England with such haste that he was forced to leave behind his luggage. His expenses claim for lost items became a Fleet Street legend: "Camel-hair overcoat (two years' wear), fifteen guineas; Dunhill pipe (two years old, and all the better for it), one pound ten shillings." It is a measure of his reputation that the Times compensated its star correspondent for the loss of an old pipe. Philby was a fine journalist, but his ambitions lay elsewhere. He wanted to join MI6, but like every would-be spy he faced a conundrum: how do you join an organization to which you cannot apply, because it does not formally exist?

In the end, Philby's entry into the secret services turned out to be as straightforward as that of [Nicholas] Elliott, and by much the same informal route: he simply "dropped a few hints here and there" among influential acquaintances and waited for an invitation to join the club. The first sign that his signals had been picked up came on the train back to London after the retreat from France, when he found himself in a first-class compartment with a journalist named Hester Harriet Marsden-Smedley, of the Sunday Express. Marsden-Smedley was thirty-eight years old, a veteran of foreign wars, and as tough as teak. She had come under enemy fire on the Luxembourg border and witnessed the German surge across the Siegfried Line. She knew people in the secret services and was said to do a little spying on the side. She found Philby charming. She did not beat about the bush.

"A person like you has to be a fool to join the army," she said. "You're capable of doing a lot more to defeat Hitler."

Philby knew exactly what she was alluding to and stammered that he "didn't have any contacts in that world."

"We'll figure something out," said Hester Marsden-Smedley.

Back in London, Philby was summoned to the office of the foreign editor of the Times, to be told that a Captain Leslie Sheridan of the "War Department" had called, asking if Philby was available for "war work" of an unspecified nature. Sheridan, the former night editor of the Daily Mirror, ran a section of MI6 known as D/Q, responsible for black propaganda and disseminating rumors.

Two days later, Philby sat down to tea at St Ermin's Hotel off St James's Park, just a few hundred yards from MI6 headquarters at 54 Broadway, with another formidable woman: Sarah Algeria Marjorie Maxse, chief of staff for MI6's Section D, which specialized in covert paramilitary operations. The D stood for "destruction." Miss Marjorie Maxse was chief organization officer for the Conservative Party, a role that apparently equipped her to identify people who would be good at spreading propaganda and blowing things up. Philby found her "intensely likeable." She clearly liked him too, for two days later they met again, this time with Guy Burgess, an old friend and Cambridge contemporary of Philby's who was already in MI6. "I began to show off, name-dropping shamelessly," wrote Philby. "It turned out I was wasting my time, since a decision had already been taken." MI5 had conducted a routine background check and found "nothing recorded against" him: young Philby was clean. Valentine Vivian, the deputy head of MI6, who had known Philby's father when they were both colonial officials in India, was prepared to vouch personally for the new recruit, giving what may be the quintessential definition of Britain's old boys' network: "I was asked about him, and said I knew his people."

Reprinted from "A Spy Among Friends" by Ben Macintyre. Copyright © 2014 by Ben Macintyre. Published by Crown Publishers, an imprint of the Crown Publishing Group, a division of Random House LLC, a Penguin Random House Company.