Dr Adeshead presents an eye-opening window into the realities of the field of forensic psychiatry. With her co-author Eileen Horne, she presents eleven anonymised case studies looking at crimes ranging from homicide to arson to assault. As much as this book is about the realities of her profession, it is about the people it serves. 

It is a widely acknowledged fact that, when compared to the outside world, a disproportionate percentage of the prison population suffers from a form of mental illness. Dr. Adshead’s emphasis on the loss of identity following a criminal act, as well as the trauma of incarceration itself, is a constant across the case studies she presents. 

Throughout the book she displays a remarkable compassion for her patients, demonstrating an ability to see beyond—whilst not excusing—the crimes committed by these patients. Repeatedly she places emphasis on the psychological harm of crime not just on its victims but on its perpetrators too. I found this incredibly thought provoking, despite being something most readers would recoil from. 

Adshead is critical of the state of mental health services up and down the country. She repeatedly acknowledges that the help afforded to these offenders could seldom be accessed by their victims and those otherwise traumatised by their crimes. In some instances she even highlights that had this care been accessible to these offenders previous to the offence, these tragedies could possibly have been prevented.

As we know, the rate of crime in this country is on the rise and our prison population now outweighs the spaces available. Furthermore, reintegration of prisoners to the community is often unsuccessful leading to career criminality. Adshead posits that access to therapy, whilst perhaps not the most popular use for public funds, provides a more practical solution to high rates of recidivism. 

Her background in attachment theory, a popularly misunderstood concept within developmental psychology, is clear from her approach in working with her patients. I found it fascinating how she related this with her ‘bicycle lock theory’. 

The Devil You Know is not the first book to attempt an understanding of the unthinkable. Where Adshead finds greater success is in her clinical narrative which dissuades the voyeuristic. This tone when paired with an unflinching willingness to look at the most maligned criminal acts affords a rare and fresh perspective for the reader to see the factors which make these ‘evil’ deeds possible.