In one of the 130 newly declassified CIA documents, a memo details the spy agency's secret plan to undermine the Soviet Union—using the novel Doctor Zhivago. The Russian novel, by poet Boris Pasternak, was banned in the Soviet Union and thus seen as a potential weapon by the CIA with "great propaganda value, not only for its intrinsic message" but also because it gave the West "the opportunity to make Soviet citizens wonder what is wrong with their government" when it bans books like it. The plot to print and distribute the Nobel Prize-winning work through Dutch intelligence services was monitored by individuals as high up as CIA Director Allen Dulles. The first part of the operation involved copies of the book being passed out behind a curtain at the Vatican pavilion at the 1958 Brussels Universal and International Exposition. The CIA believed the book's "humanistic message" posed a challenge to the Soviets.