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In page Christopher Curwen:

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Curwen spent three years as SIS liaison officer in Washington D.C. from 1968 and was then head of station in Geneva.[3] He was deputy to Sir Colin Figures from 1980 and succeeded him as Chief of the Service in 1985.[4] His tenure was notable for the successful exfiltration from Moscow of the KGB officer and British agent Oleg Gordievsky.[5]