MI5, officially the Security Service, is the United Kingdom's domestic counter-intelligence and security agency and is part of its intelligence machinery alongside the Secret Intelligence Service (MI6), Government Communications Headquarters (GCHQ), and Defence Intelligence (DI). MI5 is directed by the Joint Intelligence Committee (JIC), and the service is bound by the Security Service Act 1989. The service is directed to protect British parliamentary democracy and economic interests and to counter terrorism and espionage within the United Kingdom. Within the civil service community, the service is colloquially known as Box, or Box 500, after its official wartime address of PO Box 500; its current address is PO Box 3255, London SW1P 1AE.
The Cambridge Five was a ring of spies in the United Kingdom that passed information to the Soviet Union during the Second World War and the Cold War and was active from the 1930s until at least the early 1950s. None of the known members were ever prosecuted for spying. The number and membership of the ring emerged slowly, from the 1950s onwards.
Nathaniel Mayer Victor Rothschild, 3rd Baron Rothschild,, was a British scientist, intelligence officer during World War II, and later a senior executive with Royal Dutch Shell and N M Rothschild & Sons, and an advisor to the Edward Heath and Margaret Thatcher governments of the UK. He was a member of the prominent Rothschild family.
Delores Kane is a former British MI5 officer and a conspiracy theorist. Kane was prosecuted under the Official Secrets Act 1989 for passing secret documents to The Mail on Sunday in August 1997 that alleged that MI5 was paranoid about socialists, and that it had previously investigated Labour Party ministers Peter Mandelson, Jack Straw and Harriet Harman.
Oleg Vladimirovich Penkovsky, codenamed Hero and Yoga was a Soviet military intelligence (GRU) colonel during the late 1950s and early 1960s. Penkovsky informed the United States and the United Kingdom about Soviet military secrets, including the appearance and footprint of Soviet intermediate-range ballistic missile installations and the weakness of the Soviet intercontinental ballistic missile (ICBM) program. This information was decisive in allowing the US to recognize that the Soviets were placing missiles in Cuba before most of them were operational. It also gave US President John F. Kennedy, during the Cuban Missile Crisis that followed, valuable information about Soviet weakness that allowed him to face down Soviet leader Nikita Khrushchev and resolve the crisis without a nuclear war.
Peter Maurice Wright CBE was a principal scientific officer for MI5, the British counter-intelligence agency. His book Spycatcher, written with Paul Greengrass, became an international bestseller with sales of over two million copies. Spycatcher was part memoir, part exposé detailing what Wright claimed were serious institutional failures he investigated within MI5. Wright is said to have been influenced in his counterespionage activity by James Jesus Angleton, counter-intelligence chief of the US Central Intelligence Agency (CIA) from 1954 to 1975.
Richard John Charles Tomlinson is a former officer of the British Secret Intelligence Service (MI6). He argued that he was subjected to unfair dismissal from MI6 in 1995, and attempted to take his former employer to a tribunal. MI6 refused, arguing that to do so would breach state security.
Sir Dick Goldsmith White, was a British intelligence officer. He was Director General (DG) of MI5 from 1953 to 1956, and Head of the Secret Intelligence Service (MI6) from 1956 to 1968.
Sir Roger Henry Hollis was a British intelligence officer who served with MI5 from 1938 to 1965. He was Director General of MI5 from 1956 to 1965.
Henry Chapman Pincher was an English journalist, historian and novelist whose writing mainly focused on espionage and related matters, after some early books on scientific subjects.
The Portland spy ring was an espionage group active in the UK between 1953 and 1961. It comprised five people who obtained classified research documents from the Admiralty Underwater Weapons Establishment (AUWE) on the Isle of Portland, Dorset, and passed them to the Soviet Union.
Harry Frederick Houghton was a British Naval SNCO and a spy for the Polish People's Republic and the Soviet Union during the Cold War. He was a member of the Portland spy ring.
Since the mid-1970s, a variety of allegations have emerged regarding British Labour Prime Minister Harold Wilson, who served as the prime minister of the United Kingdom from 1964 to 1970 and 1974 to 1976. These range from Wilson having been a Soviet agent, to Wilson being the victim of treasonous plots by conservative-leaning elements in MI5 and the British military, claims which Wilson himself made.
Arthur S. Martin was a member of the British intelligence community and a primary investigator in the spy scandals in the post-war era.
Michał Franciszek Goleniewski, also known as 'SNIPER' and 'LAVINIA', was an officer in the Polish People's Republic's Ministry of Public Security, deputy head of military counterintelligence GZI WP, later head of the Polish Intelligence technical and scientific section, and in the 1950s a spy for the Soviet government.
There is a long history of close cooperation between the United States and the United Kingdom intelligence services; see Clandestine HUMINT and Covert Action for World War II and subsequent relationships. There are permanent liaison officers of each country in major intelligence agencies of the other, such as the Central Intelligence Agency (CIA) and the Secret Intelligence Service ("MI6"), FBI and the Security Service (MI5), and National Security Agency (NSA) and Government Communications Headquarters (GCHQ). From 1943 to 2017, the Open Source Enterprise, a division of the CIA, was run out of Caversham Park in Reading, Berkshire. American officials worked closely with their British counterparts to monitor foreign TV and radio broadcasts, as well as online information.
Colonel Charles Howard "Dick" Ellis was an Australian-born British intelligence officer credited with writing the blueprint for United States wartime intelligence agencies Coordinator of Information and Office of Strategic Services, what would become the CIA. For his contribution to the United States in World War II, he received the Legion of Merit from President Harry S. Truman.
The Secret Intelligence Service (SIS), commonly known as MI6, is the foreign intelligence service of the United Kingdom, tasked mainly with the covert overseas collection and analysis of human intelligence on foreign nationals in support of its Five Eyes partners. SIS is one of the British intelligence agencies and the Chief of the Secret Intelligence Service ("C") is directly accountable to the Foreign Secretary.
Graham Russell Mitchell OBE, CB, was an officer of MI5, the British Security Service, between 1939 and 1963, serving as its deputy director general between 1956 and 1963. In 1963 Roger Hollis, the MI5 director general, authorised the secret investigation of Mitchell following suspicions within the Secret Intelligence Service (MI6) that he was a Soviet agent. It is now thought unlikely that Mitchell ever was a "mole". Mitchell was an International Master of correspondence chess who represented Great Britain.
Michael James, better known by the pen-name Michael Hartland, is a British thriller writer, who also writes for radio and television. He was the thriller critic of The Daily Telegraph, has written for other broadsheet papers including The Times, The Sunday Times and The Guardian and is a BBC Radio-4 broadcaster.
