Book excerpt: "When I interrogate a serial killer I dive into the blackness of his soul. I am familiar with his feelings of emptiness, loneliness, depression, death, omnipotence and fear. I dive deeply to get a grip on his torment..." A profiler who wants to understand the mind of the serial killer must have been prepared by life experiences before he or she can dare to venture into the abyss. A person who has led a protected life will not survive.