In this paper I examine the theme of murder in Paul Thomas Anderson's 2007 film There Will Be Blood, and address the question of what lies behind the protagonist's apparent compulsion to kill his rivals. Making use of some ideas of Jacques Lacan and the Lacanian Serge Leclaire, I connect the compulsion to murder to the never-ending and ultimately impossible task of killing a child: namely, the ideal image of the wonderful child who we were required to be in the eyes of others, a task in which we must engage in order to live a creative and fulfilling life, and which lies at the heart of the psychoanalytic enterprise.