Author Marissa A. Harrison, a long-time research psychologist, describes her journey to writing Just as Deadly: The Psychology of Female Serial Killers. She recounts her pathway to conducting research on female serial killers (FSKs) and broadly introduces the concepts, content, and approach to writing this book. She describes her work with fellow researchers in various explorations of the psychology of serial murder and introduces her published work in scientific journals such as Evolutionary Behavioral Sciences, The Journal of Forensic Psychiatry and Psychology, and Current Psychology. Harrison describes her team’s work on morbid curiosity and protective vigilance, thought to motivate the great interest in serial murder. Included is a case study of Amy Archer-Gilligan to illustrate how FSKs can be just as deadly as male serial killers (MSKs). The author underscores the mandate for proper attribution of others’ work in scientific writing and her endeavors to provide extensive documentation for all factual information in this book to ensure a science-based presentation.

The topic of mental health in female serial killers (FSKs) has been largely unexamined. It is plausible that many FSKs committed their crime before the introduction of standard diagnostic systems. The author’s team found that nearly 40% of FSKs in their study sample had a history of mental illness, including anxiety, depression, personality disorders, dissociative disorders, and factitious disorder imposed on another (FDIA), formerly called Munchausen syndrome by proxy (MSBP). This evidences that mental illness is overrepresented in FSKs compared to the population. Also in this chapter, the author reviews data on infrequent FSK mental health treatment, as well as on demeanor, sexual adjustment, and substance use. The author urges increased efforts for diagnosing and treating mental health issues to prevent murder. Case studies of FSKs Martha Woods and Marybeth Tinning illustrate mental health phenomena. The case of FSK Margie Barfield and a revisitation of the case of FSK Amy Archer-Gilligan illustrate substance abuse.