Number Six vows revenge and goes after a sadistic Number Two after he drives a fellow Village resident to her death.
Number Six is incensed when he witnesses the suicide of Number Seventy-Three who has been brutally interrogated by Number two and he informs Number Two that he will avenge her death. He begins a war of nerves,leading Number Two to believe that he is Agent D6,employed by a superior called XO4, and making him fear that he is in danger. Ultimately the prisoner is triumphant as yet another Number Two resigns.
The new Number 2 is cruel and seems to be something of a sadist. He browbeats a Village resident into jumping from her hospital window and Number 2, who has witnessed the scene, decides to take him on. Number 6 plants evidence for Number 2 to find that suggests Six is actually an agent in the Village to observe Number 2 and report on his stability. Number 2 grows increasingly paranoid, distrusting everyone around him accusing them of lying and plotting against him. As Number 6 continues to plant false clues and red herrings, Number 2 simply goes mad.
- Another quiet day in the Village is shattered by a woman's screaming. No. 6, walking past the so-called hospital, rushes in to see what all the commotion is about, and when he bursts into a young woman's room, he takes in at a glance the sadistic torture that No. 2 is using on her. Distracted for a brief moment by No. 6's arrival, the woman pushes past her tormentors and leaps out of the window to her death. No. 2 turns icily to No.6 and glares at him.
"You'll regret that, No. 6" he hisses.
"No" replies the Prisoner, leveling a murderous look at No.2. "You will."
So begins a game of cat-and-mouse, a battle of wills between the twisted No.2, and the determined No.6.