Detailed Explanation
Arthur Mitchell, the Trinity Killer, is considered one of the most terrifying villains in television history. Played brilliantly by John Lithgow (who won an Emmy for the role), Arthur presents himself as a kind, religious family man who builds homes for Habitat for Humanity. In reality, he's been killing for 30 years in a ritualistic cycle: first a young woman in a bathtub (representing his sister), then a mother who jumps to her death (representing his mother), and finally a father bludgeoned with a hammer (representing his abusive father). His kill count exceeds 250, making him far more prolific than Dexter himself.