8. Arthur Mitchell/The Trinity Killer - Dexter
A family man by day, and a serial killer by night. John Lithgow is probably one of the more sadistic villains on this list. Taking his victims into the bathtub, he slices their femoral artery and just waits there, watching as they bleed out into the warm tub water. The Trinity Killer has a very unassuming look about him. Some villains are casted to look as if they are meant to be a villain but not this one. I would have never guessed what Arthur Mitchell was up to if I saw him on the street. There is one particular Trinity Killer moment in the show that I found memorable. He follows a family out of their car and reads the stick figure family decals on the back. Using the names he got off of the back of the car he tricks a young boy into accompanying him back to his van and ultimately kidnaps him. SMART!