Vasili Mitrokhin , a senior archivist in the KGB, smuggled documents out of the KGB archive, which, when published, were described by the FBI as constituting "the greatest single cache of intelligence ever received by the West." Now, intelligence expert Christopher Andrew is publishing the second series of potentially explosive revelations in The Mitrokhin Archive: The KGB in the World. Paul Allen and guests assess the impact this will have on our understanding of the Cold War. Producer Fiona McLean