When the Devil Knocks is the intimate story of a woman suffering from Dissociative Identity Disorder, formerly known as Multiple Personality.
Joseph Campbell has said that the psychotic is drowning in the waters in which mystics love to swim. This is a realm of mind/spirit that is part of our being human. And the psychotic can and does often find his/her way out. One need not stay drowning.
I've done several posts on this book because the idea it's covering is very important. We are exporting our very poor understanding of the psyche to other cultures. There are several other posts on this blog that comments or shares info on this book, look here.