The Bio Wars

Khrushchev loosened the restrictions on art, literature and cinema - allowing, among others, the (very) critical novel Dr Zhivago to be published. He also did away with arbitrary state terror - lessening the excesses of Stalinism. He also continued the massive apartment building programme begun to house the people and to help alleviate the hardship caused by the war. For the religious, however, he undertook a massive clampdown on the church. People were required to register to attend, and church-going would bar you from party membership, from promotion, from better housing and your children would not be able to get into the better schools. He also undertook to destroy many churches - notably the Church of Christ the Saviour in Moscow and the destruction of three cathedrals in Lenin's birthplace of Ul'ianovsk.
You must mention the Virgin Lands Scheme - where millions of acres of steppe were put to the plough to grow maize (corn if you are an American). This was initially very successful, but, like many of his schemes, it soon failed due to poor planning and lack of investment.

Brezhnev saw the Khrushchev thaw re-freeze - censorship was reimposed, the terror was not re-imposed, although imprisonment, exile and being held in a secure asylum for the most dangerous dissidents was common. Religion was still clamped down on - although under Brezhnev the focus shifted to a clampdown on the Jewish population - leading to many wanting to emigrate to Israel (most were refused - they became known as the Refuseniks). In the mid 1970s Brezhnev began to change the economic base of the country, away from heavy industry beginning light, consumer industries. One reason for this was that the Soviet Union was doing well at the Olympics, so they wanted people to see the success on the television. He also invaded Afghanistan - leading to many young men being killed and injured in the conflict - and, with the ongoing failure to subdue the Afghans - the regime appeared to many