Every day six people in the United States are murdered by spouses or intimate partners. The stories of killer spouses tend to captivate us, as they beg the question of how so many seemingly normal and happy people manage to go over the edge. Indeed, every relationship presents "extreme moments" where scary feelings surface, yet what happens when those feelings turn to action? In "Till Death Do Us Part," noted psychotherapist Dr. Robi Ludwig, along with journalist Matt Birkbeck, presents the psychological profiles of notorious killer spouses -- from Scott Peterson and Clara Harris to Rabbi Fred Neulander and Betty Broderick.