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Mata Hari (1876–1917) -

Mata Hari was born Margaretha Geertruida Zelle in the Netherlands. She gained notoriety after moving to Paris where she became an exotic dancer, sometimes only wearing a gold bejeweled bra and jewelry.

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Mata Hari -

During World War I, she spied for the Germans. Eventually arrested by the French, she was executed by firing squad. Apparently she blew a kiss before the volley of shots rang out.

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Julius Rosenberg - They were also accused of transmitting nuclear weapon designs to the enemy. While Julius was recruited by Moscow as a courier and recruiter for the Soviets, Ethel was more of an accessory. Charged with espionage, the couple were found guilty and executed by electric chair.

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Aldrich Ames (1941– ) - Ames spent 31 years with the Central Intelligence Agency (CIA) as a counterintelligence analyst, ending up in Washington, D.C. with access to CIA plans and operations against the KGB and the GRU (Soviet military intelligence).

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Aldrich Ames - In debt after a divorce settlement, Ames began spying for the USSR, betraying CIA operatives, and collecting vast amounts of money for doing so. In 1994, Ames and his second wife were arrested. He pleaded guilty to espionage charges and was sentenced to life imprisonment without parole. She was jailed for tax evasion.

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Klaus Fuchs (1911–1988) - German-born Fuchs was interned in Canada during the early years of World War II, but by 1943 he was working in the US on the top-secret Manhattan Project.

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Klaus Fuchs - After the war, he returned to the UK and was employed by the Atomic Energy Research Establishment. Exposed as a Soviet spy in 1950, he served nine years in prison after which he emigrated to East Germany.

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Virginia Hall (1906 –1982) - An American citizen, Hall became a spy with the British Special Operations Executive during World War II. She operated in France, working with the French Resistance. She ended up on the Gestapo's most wanted list.

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Virginia Hall - Hall later joined the US Office of Strategic Services (OSS), again working in France until the end of the war (she's pictured receiving the Distinguished Service Cross in 1945 from OSS chief General Donovan). She ended her career as a CIA intelligence analyst.

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Frederick "Fritz" Joubert Duquesne (1877–1956) - A South African Boer, Duquesne fought against the British Empire in the Second Boer War and operated as a US-based German secret agent during both World Wars.

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Frederick "Fritz" Joubert Duquesne - During World War II, while living in New York, he headed the infamous Duquesne spy ring, a German espionage network. The ring was eventually closed down by the FBI, and Duquesne served 14 years in Leavenworth Penitentiary, Kansas.

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John André (1750–1780) - A British Army officer serving in America during the American Revolutionary War, André took charge of British Secret Service operations in 1779.

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John André - After assisting defecting American military officer Benedict Arnold in his attempt to surrender the fort at West Point to the British, André was captured and hanged as a spy by the Continental Army. Pictured: a self portrait of André drawn on the eve of his execution.

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Sidney Reilly (c. 1873–1925) - A Russian-born British secret agent, Reilly, often referred to as the "Ace of Spies," was employed by the British police force's Special Branch and later the British Secret Service Bureau, the precursor of the UK's modern MI6.

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Sidney Reilly - A well-traveled adventurer in his youth, Reilly began his espionage activities in 1890s London Russian émigré circles. Dispatched to Soviet Russia in 1925, Reilly was captured and executed. Today he is synonymous with the myth of the British "spook" or super-spy.

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Anthony Blunt (1907–1983) - A leading British art historian and Surveyor of the Queen's Pictures, Blunt was probably recruited to spy for the Soviet Union by the People's Commissariat for Internal Affairs (NKVD) during a visit he made to Moscow in 1934.

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Anthony Blunt - Blunt served as a member of the British Army's intelligence corps during World War II, when he was recruited by MI5, the Security Service. A member of the infamous Cambridge Five spy ring, Blunt confessed to being a Soviet spy as early as 1964, after being offered immunity from prosecution. He was publicly unmasked in 1979 but was never jailed.

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Kim Philby (1912–1988) - A contemporary of Blunt's at Cambridge University, Philby became a high-ranking member of British intelligence. It's possible that Philby's first wife, Litzi Friedmann, an Austrian Communist, recruited him to the Soviet cause.

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Kim Philby - As an MI6 operative during and after World War II, Philby had access to top-secret material, which he passed on to his NKVD handlers. He arrived in Washington, D.C. in 1949. Increasingly under suspicion by the CIA, Philby eventually defected to the USSR from Beirut. He died in Moscow and was given a hero's funeral.

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Krystyna Skarbek (1908–1952) - One of the longest-serving of all Britain's wartime women agents, Polish-born Skarbek worked with the Special Operations Executive and successfully carried out numerous undercover missions in Nazi-occupied France and Poland. Adopting the name Christine Granville postwar, her exploits were recognized with the award of the George Medal, an OBE (Officer of the Order of the British Empire), and the Croix de Guerre. Sadly, she was murdered in a London hotel by an obsessed stalker who was ultimately hanged for his crime.

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George Blake (1922–2020 ) - Born George Behar in the Netherlands, Blake, who later became a British national, served with the Royal Navy during World War II before being recruited by MI6 and serving in the Dutch Section.

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George Blake - In 1948, he was posted to Seoul, South Korea. During the subsequent Korean War, he was taken prisoner by Communist North Korean forces and later volunteered to work for the Soviet Union's spy service, the KGB. Released in 1953, he spied for the USSR until 1961, when his treachery was discovered. Later jailed for 42 years, Blake escaped from prison and fled to Moscow, where he lived until his death.

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Duško Popov (1912–1981) - Popov was a Serbian double agent who ended up working for Britain's Secret Service Bureau (MI6) during World War II and passing off disinformation to Germany's military intelligence service, Abwehr. He survived the war but died at 69 of ill health.

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Duško Popov - Interestingly, James Bond creator Ian Fleming is said to have based his fictional spy's code number, 007, on Popov's uncle's phone number, 26-007.

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Donald Maclean (1913–1983) - Another member of the so-called Cambridge Five spy ring, Maclean was recruited by the Russian NKVD while still at university.

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Donald Maclean - Later as a topflight diplomat, he kept the Soviets informed of the West's activities while stationed in Paris and then after World War II broke out, in London. He fell under suspicion while in Washington, D.C. and it was the Russians who eventually urged him to defect, in 1951.

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Julius (1917–1953) and Ethel (1916–1953) Rosenberg - The Rosenbergs, United States citizens, were accused of providing top-secret information about sonar, radar, and jet propulsion engines to the Soviets during the Cold War.

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Guy Burgess (1911–1963) - Also recruited by Moscow while at university and destined to become part of the Cambridge spy ring, Burgess joined the BBC as an assistant producer before being employed by MI6.

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Guy Burgess -

He joined the Foreign Office in 1944 and fed his Soviet handlers a goldmine of classified information. Burgess was also posted to Washington, D.C., and was assigned work of top-secret sensitivity. Burgess defected to the Soviet Union with Donald MacLean. Incidentally, the fifth member of the Cambridge spy ring was John Cairncross.

See also: The dark history of secret police

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