In 1962, Soviet Premier Nikita Khrushchev is overthrown by a cabal of hard-liners angry over Khrushchev's failure to act to prevent the U.S. from occupying Cuba and deposing its leftist president Fidel Castro in April 1961 and what they see as his 'weakness' in the Berlin crisis of that fall.

Some, in addition, still nurse bitterness over the Premier's denunciation in 1956 of Stalin-era 'excesses,' which they do not regard as excesses at all.

Khrushchev's fall will be followed by a period of 'troika' rulership which will last until March 1964, when Communist Party apparatchik Leonid Brezhnev will finally consolidate his position as the Soviet Union's supreme leader.