During the Cold War in the 1960s, British spy Alekrimas (Richard Burton Richard Burton) was stationed in West Berlin for years to engage in espionage. However, after witnessing that his colleagues lurking in East Germany were shot and killed by East German border guards, Alek returned to the headquarters of the British Secret Service to accept the ultimate secret mission. In order to blend in with East Germany, Alek deliberately exposes his weakness, even his depraved side, in order to alienate the relationship between the head of East German intelligence, Moonte (Peter Van Eyck Peter van Eyck) and his subordinate Fydler (Oscar Venel Oskar Werner) and disintegrate its power. However, under the complicated and confusing mask of double agents, Alek gradually found that he was just an insignificant pawn, and Alek was tortured by the inner moral judgment and the increasingly blurred distinction between good and evil. This film is adapted from the spy novel of the same name published in 1963. The film won six awards and four nominations, and Richard Burton, the leading actor, was nominated for best actor at the 38th Academy Awards in 1966.