This book has been written by two brothers, one a consultant clinical psychologist, the other a writer and editor. This creative mix has produced a popular scientific account of the social and clinical phenomenon of paranoia. The book has an engaging style that suits its intended audience. Readers are not burdened with specific references, yet the academic sources for each chapter are provided.

The authors are keen that paranoia should be understood as part of general experience rather than just psychiatric illness. Perhaps this should not be seen as a surprising perspective. After all, Melanie Klein regarded persecutory anxiety as having its origin in the infant's fear of retaliation of the ‘bad breast’, with such psychotic thinking being retained into adulthood. The authors struggle, though, with what they regard as messy, complex psychoanalytic explanations. They refer to Freud's analysis of paranoid delusions as the consequence of repressed homosexual urges, yet they favour the commonsense view that unfounded mistrust exists generally among a substantial minority of people (this is supported by the authors' study of reactions to a virtual reality underground train ride). Paranoia is hence for them an everyday, emotional concern that is associated with anxiety, depression, worry, interpersonal sensitivity and negative ideas about self.

The authors speculate that paranoia is increasing, although admittedly there is no historical evidence for comparison. They blame social factors such as urbanisation, social isolation, migration, trauma and victimisation; they also mention mistrust of authority and media effects on assessment of risk. They do not explicitly set this in the context of the ‘risk society’. However, the view that the role of government is to manage risks on behalf of the citizens has led to increased accountability across society that is not always sensibly applied. But the modern emphasis on ensuring accountability does not necessarily mean there has been an increase in paranoid thinking.

The book characterises our society as one in which we do not let our children out unsupervised for fear they will be abducted by a paedophile. A summary of six steps for cognitive–behavioural therapy for this new age of paranoia is included. Overall, I found the book enjoyable and educational, but I would not make as much of the issue of paranoia as the authors do, particularly when they suggest that there should be government intervention to combat the issue. None the less, we need reminding that we are not always as rational as we might think we are. It may not be the menace the authors suggest it is, but their engagement of public interest in the subject of paranoia is to be welcomed.