There are many theories in relation to serial killers, some theories stem from the killers upbringing while other theories focus on their social skills and how they functioned in society. Some concepts go as far as religious aspects like that of demonic possession, the battle of good and evil, or mental illness like schizophrenia. However, the Biopsychosocial Theory is a combination of biological, psychological, and social factors that come together like ingredients to form the mind of a serial killer