Many thousands of books have been written about Lenin: apologetic, enthusiastic, sugary. The author of this work himself was for a long time greatly influenced by the ideas of Lenin. But deep familiarization with the hitherto closed archives of the Politburo, the Central Committee of the CPSU, and other previously unknown materials gradually led the author to a deeply conscious conclusion: in the 20th century, all the main troubles of Russia came from Lenin and the organization he created, with an extremely cruel philosophy.