The book is a study of the personalities of totalitarian criminals (mainly the so-called leaders), serial sexual killers, terrorists, as well as those who committed murders repeatedly due to domestic conflicts, for hooligan or selfish motives. The general reasons for their most dangerous criminal actions and the common distinctive features inherent in these individuals are revealed. The work is based on extensive empirical material from many years of specific research carried out personally by the author. A detailed analysis of the personality of individual criminals and the motives of their behavior is given. Written in simple, accessible language. Designed for a wide range of readers: students, graduate students, teachers and researchers, including lawyers, psychologists and psychiatrists - everyone who seeks to understand the causes of the most dangerous phenomena in our social life.