ANDREW BOYLE came to town recently to discuss and promote his book, which has caused something of a furor in England. Titled The Climate of Treason there, and The Fourth Man here (see review, page 1), the book's exposure of the "Fourth Man" in the Burgess-Maclean-Philby spy case as a man named "Maurice" caused questions to be raised in Parliament and caused Prime Minister Margaret Thatcher to reveal Maurice's identity as Sir Anthony Blunt, a knighted art curator to Queen Elizabeth.

"Margaret Thatcher is not my literary agent," says Boyle laughing. "People suggest she is, but she ain't. But I do admire her. It took a woman to do it. We've had, how many prime ministers? Seven? None of these gentlemen would have done what she did, because the policy was otherwise. tShe threw it out of the window, very gracefully, very correctly, even though it did put the queen in dutch. It had to be done to change that policy, because it let a bit of fresh air in."

Now that the fourth man has been identified, how about a fifth man or a sixth? "There was a man who was a friend of Burgess since 1932, Goronwy Rees. He was the man whom, in a drunken moment in 1936, Burgess tried not only to inveigle into the Communist party, but to recruit as a Soviet agent. At that time Burgess revealed himself to Rees and gave him one other name, Anthony Blunt. From 1936 to 1951, Rees never said a word. He knew that M15 were not interested in upper-class radicals. The ones they thought of as Communists were the menials, the lowest of the low, the ones with grievances against society. The upper-class members of the C.P. got away with murder. That's the 'climate of treason.' Now, all through the war Rees was an active soldier; he became an officer on the staff of Field Marshall Montgomery. And, rather like a tired businessman going to a strip club, he used to go to this extraordinary flat which Burgess kept. It was a hive of Comintern and KGB activities. All sorts of people used to drop in -- members of Parliament, people from Whitehall, you name them, all dropping in. It was a cleverly orchestrated thing, because Burgess was like a queen bee. Now, after the war, when came the crucial time for Burgess to disappear, he put in a drunken call -- or it sounded drunk -- to Goronwy Bees' wife. He kept saying, "Tell Goronwy I am about to do something that will be misunderstood by the whole world but which I think Goronwy will understand.' When his wife gave him the message, Rees shrunk with horror and said, 'God, he's gone to Moscow!' Now this wasn't based on any inside information; it was just a wild, irrational jump in the dark. To prove his own honesty, Rees called someone he knew in M16, and this man said, 'I'd like you to get onto Guy Liddell in M15.' Liddell invited him to lunch; Rees accepted, and there was another guest there . . . Anthont Blunt. And the two men did their damnedest, together, to dissuade Rees from going to M15 and 'making a fool of himself.' But Rees went anyway."

Was Liddell the fifth man? "I would like to think that he was just another blundering idiot -- there are so many around. I wouldn't say that he was the fifth man. I would say that he was either remarkably stupid or that what he did was uncommonly sinister. And the words are not mine, they're Rees'. Liddell was married to a daughter of the Baring banking family. And he fought bravely in the First World War. He was a veteran of M15, he'd been there since '31; he was a professional. And there are people in the service, still alive, who regard him as their mentor. Yet during the Second World War, after the break-up of his marriage, Liddell appeared a great deal at the flat I tried to describe. He was a constant habitue of that flat, at which all sorts of things were divulged, talked about, orchestrated. Degrees of complicity go on and on, and you can't get to the end of it, but Liddell was a constant person, often there, in regular attendance."

Why was the Blunt story buried so long. "Well, the British are obsessed with secrecy, aren't they? And there's one law for the Blunts and another for the Blakes, isn't there? That's what the Labour Party tries to drum up, and it looks horribly like it. I suppose as a member of the royal family got involved in that, they'd protect the royal family as long as they could. But I think it's totally inexcusable that the queen should have been dragged into this. I think it's very, very much against the grain of feeling in Britain that the head of state, who is supposed to be above the battle, should be dragged into it."

Did the queen know? "Well, Malcolm Muggeridge, who is a great friend of mine, takes the view that there are ways and ways of telling people -- courtiers' ways which do not necessarily tell all. 'You know, Ma'am Anthony's been keeping rather strange company. Perhaps we'd better have him to tea in the castle,' etc. I don't know; perhaps it was said that way. It might have been delayed. It might have been softened. Anyway, Blunt was kept on."

How far does it reach and how high up does it go? "It goes a long way up. It's rather like a sardine tin, you open it and see a little bit, and then a little bit more. By the way there's no truth in what Malcolm Mugeridge said at a literary luncheon that I want to be Keeper of the Queen's moles." er.

The winning entry will be the first correct answer drawn at random.

Employes of The Washington Post Company and their families are not eligible to enter.

Entries must be received no later than February 11.

The winner's name and city of residence will be announced in the February 17 Book World.

A Washington Post Book World book bag will be sent each week to the winner. Book Bag XXII:

Question: These American novels take their titles from phrases in the works of three poets. Name the poets and the works in question. "Tender is the Night," by F. Scott Fitzgerald "For Whom the Bell Tolls," by Ernest Hemingway "The Sound and the Fury," by William Faulkner

Answer: "Tender is the Night" is from "Ode to a Nightingale," by John Keats; "For Whom the Bell Tolls" is from "Meditation No. XVII," by John Donne; "The Sound and the Fury" is from Shakespear's "Macbeth." The winner: Anzy Wells of the District.