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Zak is a schizophrenic in an insane asylum for murdering his parents and other people along the way. He has little to no sense of morality and doesn't quite understand what he is doing is wrong.

Reese is more methodical, but just as insane when it comes to easily ending a human life. He has a game he likes to play. A Hunt and be Killed game. And he never looses.

However, Reese didn't count on one of his random targets on the street be an escaped mental patient that can match him in a fight.