This book is the memoirs of one of the best criminologists in Russia at the beginning of the 20th century, who was once in charge of the entire criminal investigation department of the Russian Empire. The book describes the most high-profile and scandalous cases from his practice: jewelry thefts and the mystery of the pink diamond, robbery and millions of monks, murders of famous officials and merchants, marriage scams and major frauds; psychology of blue blood hunters; cheaters' secrets and the secrets of the red-haired undertaker. The entire dark side of Russian life before the revolution appears from the pages of the book frankly and impartially, and the “lost souls of Russia” are also depicted. And all this is the real truth.