Inspector Abhiraj Sen is a powerful officer of the Homicide Section of the Crime Branch of the Kolkata Police. His method of investigation is very different from that of the other five police officers. He has immense faith in himself. While analyzing the cause of each case, on the one hand, he interrogates the suspects thoroughly, and on the other hand, he uses the benefits of the scientific method to create a link between crime and criminality. It is in this way that he creates a path that solves one murder case after another in the heart of Kolkata. This book is not only a description of the unraveling of the mystery, but also the events that have happened in Kolkata in the recent past and have been published in the newspapers, slightly changing them depending on the place, time, and context. This book contains a total of two novels, a novella and a long story. In each writing of this book, the darkness hidden deep in the human mind and the instincts of guilt mixed in that darkness are highlighted.