The book is dedicated to Leningrad police officers who investigate dangerous criminal crimes. The authors of the book - a journalist and a police colonel - took as a basis true crime stories that happened in Leningrad several years ago, and fascinatingly told about how an organized criminal group was uncovered in one of the industrial sectors of the city, how artisans involved in criminal trade were identified, how a former lawyer was caught in a false denunciation, how two murders were solved, how the blackmailers were exposed.