Part of this un-sub's MO is to call 911 as they are committing the murder. At first it seems as though there are two men, one reluctantly begging the other to show mercy, and one cruel, holier-than-thou "muderer" (go figure?) bent on punishing sinners.
Seems there are not two men, but one man who hears his father's voice, pleads for mercy for the victims that he kills because his father's voice orders him to. Obviously terribly abused and brainwashed as a child by his father (which is shown in flashbacks that at first aren't apparent flashbacks), he's damaged. I personally believe something has to go very wrong in any serial killer's upbringing no matter what the family says. So it's believable, frightening and sad that sometimes people can become too warped for rehabilitation. Society can only protect itself from those victims aka perpetrators.
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