The narrative-based approach acts as the only tool capable of creating and assigning a meaning to individual life stories, linking individuals to their actions. The use of narrative as a reference frame for understanding the motive of the crime therefore offers an innovative perspective into criminology and its forensic application. Through the stories of the criminals and the victims, of society, and the world of justice as a whole, doing narrative criminology means listening to and accurately analysing criminal life stories to shed some light and meaning on the obscure elements of reality that from time to time take shape as a violent act. After a review of the most recent literature in the criminological narrative area, the present work analyses the role of the criminologist as an expert who provides an essential contribution during investigation and trial phases. Moreover, the work proposes the use of a narrative approach and the contribution of a narrative criminologist in two different moments of the criminal procedure: during the investigation phase, through a preventive methodological narrative training of forensic experts, with emphasis on team work, and in the trial phase through the use of criminological interviews to assess criminal liability and dangerousness.