Dark Revenge

As far as a person can go to get revenge?
Scott Hunter a man who has his life totally dedicated to work, detective City Reaven's Dake. He spends most of his time investigating cases that often escape from reality and not leave many clues; enlists the help of his partner and friend Luke Mittchell.
Scott has faced bad situations that caused him to learn many things, but all their wisdom did not prepare him for what's to come.
A disagreement in the past made an enemy that is closer than he realizes, watching him from afar expect the best opportunity to take revenge; someone who is willing to kick any stones your way.
As far as this person will be able to go to get revenge?