When the Queen’s art adviser Anthony Blunt quietly admitted in 1964 that he had been a spy for Stalinist Russia, the confession sent shockwaves through the British secret state and the royal family.



Having spent years attempting to identify the so-called “fourth man” of the Cambridge five spy ring, MI5 finally had their man.

The attorney general of the day, Sir John Hobson, had already agreed that Blunt could be offered immunity from prosecution as long as he made a full confession, and the home secretary, Henry Brooke, was fully briefed by MI5.

Discreetly, the Queen was informed about the treachery. Not only was Blunt the surveyor of the Queen’s pictures – looking after one of the largest and richest collections of art in the world – he was also her mother’s third cousin.

Unfortunately, nobody bothered to tell the prime minister, Alec Douglas-Home.

British government papers released at the National Archives on Tuesday make clear that Douglas-Home knew nothing about Blunt’s acts of betrayal until November 1979, when Margaret Thatcher stood up and exposed Blunt in the House of Commons.

Sir Anthony Blunt confessed that he was the ‘fourth man’ in the Cambridge spy ring. Photograph: PA

Thatcher’s statement, and the disclosure of the secret immunity deal, caused uproar and Blunt was stripped of his knighthood within minutes.

Shortly afterwards, Downing Street received a letter from Brooke in which he admitted to having kept Douglas-Home in the dark.

“I have written to Alec to explain why in April 1964 I did not bring him in on what was happening about Blunt,” Brooke wrote, “and to say how sorry [I am] if in my well meant effort not to add to his burdens I may, with hindsight, have exercised my discretion wrongly.”

Even then, nobody at Downing Street contacted Douglas-Home to discuss the affair. Only in 1990, after an American author began asking questions about Blunt, did an official at No 10 contact the former premier, who wrote back to say: “Thank you for your letter. My memory is pretty faulty, but I wasn’t told about Blunt’s activities before the knowledge was public property.”

Blunt had been recruited by Stalin’s NKVD agency while at Cambridge in the 1930s. In 1939 he joined the British army and the following year joined MI5.

Throughout the war he passed secret material to his handlers, before resuming his career as an art historian. In 1951, he helped his fellow traitors Guy Burgess and Donald Maclean flee the country, and a few years later put another member of the Cambridge five, Kim Philby, in touch with Soviet intelligence.

In 1964 an American citizen informed MI5 that Blunt had recruited him to the NKVD many years earlier. In April that year an MI5 officer called Blunt’s office at the Courtauld Institute, where he was director, and gave him an assurance that no action would be taken against him if he told the truth. He then made a full confession.

The fifth member of the ring, John Cairncross, was exposed shortly after Thatcher publicly identified Blunt, who died aged 75 in 1983, as the “fourth man”.