On 26th April 1986 the nuclear reactor at the fourth unit of the V.I. Lenin Power Station at Chernobyl exploded: many millions suffered, and continue to suffer from the consequences. To chronicle this disaster and its aftermath, the author interviewed the engineers and operators who were conducting the fateful test on the night of 25th April; he talked to the director of the power station, serving a ten-year sentence for negligence; and he went to the hitherto top-secret institutes once run by Beria's Ministry of Medium Machine Building - the Kurchatov Institute, Moscow's Hospital No 6 and the once-closed city of Obninsk. He has taken advantage of the declassification of nuclear information in the former Soviet Union and the loosening of tongues that followed the failure of the coup in 1991, and also gained access to the trial transcripts, the protocol of the hitherto secret Medical Commission and other confidential reports. The author has also written "Alive" and "The Train Robbers".