The Author as a dangerous man. Hungarian-born writer Koestler did time in prisons or internment camps in Franco's fascist Spain, where he was under a death sentence, in France, and later, Great Britain where he was jailed as an undesirable alien. A disillusioned Communist, he is most famous for his novel attacking Stalin's regime, "Darkness at Noon", but wrote on Science, Judaism, and the paranormal as well. He died by his own hand in 1983, suffering from both leukemia and Parkinson's. His estate established the Koestler Parapsychology Unit at the University of Edinburgh.
Koestler is the subject of a new biography which you can read about here.