Peter Maurice Wright (9 August 1916 – 27 April 1995) was the principal scientific officer for MI5, the British counter-intelligence agency. His book Spycatcher became an international bestseller with sales of over two million copies. Spycatcher was part memoir, part exposé of what Wright claimed were serious institutional failings in MI5 and his subsequent investigations into those. He is said to have been influenced in his counterespionage activity by James Jesus Angleton, the US Central Intelligence Agency (CIA) counterintelligence chief from 1954 to 1975.
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