double agent

espionage

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Last updated

June 25, 2026

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A double agent is a spy who deceives one government while secretly working for another. This term, first used in 1935, is also synonymous with "sleeper" or "counterspy."123

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Aldrich Ames
…one of the most successful double agents for the Soviet Union and Russia.
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…one of the most successful double agents for the Soviet Union and Russia.
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George Blake
…1961, he admitted being a double agent, having given every important document that had come into his possession since 1953 to his Soviet contact and having betrayed many British agents (at least 42 by his captors’ account, some 600 by his own account). Sentenced to 42 years in prison in…
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…1961, he admitted being a double agent, having given every important document that had come into his possession since 1953 to his Soviet contact and having betrayed many British agents (at least 42 by his captors’ account, some 600 by his own account). Sentenced to 42 years in prison in…
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Russia
The revolution of 1905–06
This use of double agents (or agents provocateurs, as they were often known) did much to demoralize both the revolutionaries and the police and to undermine the reputation of both with the public at large. The nadir was reached in 1908, when it was disclosed that Yevno Azef,…
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This use of double agents (or agents provocateurs, as they were often known) did much to demoralize both the revolutionaries and the police and to undermine the reputation of both with the public at large. The nadir was reached in 1908, when it was disclosed that Yevno Azef,…
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Kim Philby
…and the most successful Soviet double agent of the Cold War period.
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…and the most successful Soviet double agent of the Cold War period.
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