From The Tom Woods Show:
[Mises Institute Senior Fellow] Yuri Maltsev, an adviser to Mikhail Gorbachev’s government, tells the story of his defection to the U.S., and relates stories from his life in the Soviet Union.
While at Moscow State University, he received special permission to read forbidden, anti-communist books. He was told to take his permission letter, get in the elevator, and press the button that had no number on it. This took him to a floor with two armed librarians, who had him sign still more forms, swearing never to reveal the contents of the books he was about to read.