The new Number Two is at the Village Hospital interrogating a female prisoner, Number Seventy-Three. He asks why she cut her wrists and if she's unhappy. She denies being unhappy and says that she can't tell him anything about her husband's location. Number Two preys on her insecurity, saying that her husband is having an affair and offering to show her photographs which will prove it. When she still refuses to talk, he moves in on her. Number Six is passing by when he hears her scream. He runs upstairs to her room past the medical technicians just in time to see her throw herself out the window to her death. Number Two says he'll pay for interfering, but Number six warns him that he'll be the one to pay.
Sometime later, Number Two calls and tells Number Six to report to him. Number Six refuses but Number Two sends his assistant Number Fourteen and some Guardians to subdue Number Six and bring him along. Number Two is prepared to use physical means if necessary and threatens Number Six with a sword tip to the eyes. Number Six refuses to break and says the only thing he's feeling is disgust. Number Two slaps him and quotes Goethe, saying he'll be the hammer to Number Six's anvil. They're interrupted when Number Two's masters call. Number Six listens as Number Two nervously assures his superiors they have nothing to worry about and he's in control of the situation. Number Six leaves and Number Two orders special surveillance on him.
Number Six begins a campaign of harassment. He goes to the shop and purchases a newspaper and six copies of a record album. He circles the word "security" on the newspaper and listens to all six albums, claiming one of them is not the same. He times them carefully and then writes down a note. He gives them back to the shopkeeper and says they're not satisfactory. After he leaves, the Shopkeeper reports to Number Two and tells him what happened. Suspicious, Number Two monitors Number Six's flat and sees him write something down on a pad of paper and take the top sheet. Number Two sends Number Fourteen to the flat: both are unaware that Number Six is watching them. Number Fourteen returns with the pad and they analyse the impression to find a message saying Number Six is making a report on Number Two's stability and will provide a full report later.
That night, Number Six takes an envelope and leaves his flat and heads to the beach. Numbers Fourteen and Two follow and watch as he puts the envelope in the Stone Boat. Number Fourteen recovers it but they discover it contains nothing but blank pages. Number Two dismisses the curious Number Fourteen and orders a technician to run a check. The man finds nothing and Number Two wonders if he's hiding something from him.
Continuing his campaign, Number Six places a personal advertisement quoting Cervantes and then calls the Director of Psychiatrics. He asks the doctor for a report and the man has no idea what he's talking about. Number Six agrees it's wise not to discuss the matter on the phone and says he'll call back later. Number Two interrogates the doctor who insists he has no idea what Number Six is calling about. Number Two insists he's lying and tells him to get out.
Next, Number Six asks the band master to play the music from the album. The man doe so and then reports to Number Two, who demands to know what else Number Six said. He doesn't believe the man when he denies any further conversations. Number Six then makes a request for the Supervisor to read off a birthday greeting from a dead Villager to Number Six. Number Two seizes upon it and realises that it's not Number Six's birthday. He confronts the Supervisor and demands to know why he read the message. The Supervisor, confused, denies everything and Number Two replaces him, saying he'll break the conspiracy against him no matter what it takes.
Number Fourteen warns Number Two that Number Six is poisoning him against everyone and asks permission to deal with him permanently. Number Two warns that his masters would blame him for any "accident" but considers the matter. Number Six visits the Green Dome, saying that Number Two called him. A confused Number Two gives the nod to his assistant, who challenges Number Six to a game of kosho. They engage in combat, which grows increasingly aggressive. They're interrupted just in time as the next players arrive.
Later, Number Six purchases a notebook and a cuckoo clock, one with a wooden box with a flap. He uses the box to trap a pigeon and leaves the cuckoo clock at Number Two's doorstep. A frazzled Number Two has a bomb squad defuse it but they don't find anything.
Number Six puts a piece of paper on the pigeon's leg and releases it. A desperate Number Two has the new Supervisor shoot it down and then turns the message over to the cryptology department. The coded message says that Number Six will be sending a visual signal the next morning. They watch him as he goes to the beach and uses a mirror to flash a Morse code signal out to sea. The sensors indicate there's no boat or sub at sea, and the decoded message reads, "Pat a cake, pat a cake."
Next Number Six approaches Number Fourteen and stages a nonsensical conversation about how he slept and how walking on the beach helped his insomnia. The waiter reports the conversation and Number Two demands an explanation. Number Fourteen realises what's happening and tries to explain, but Number Two refuses to hear it and orders him out. When the Butler hesitates, Number Two fires him as well. Number Fourteen goes to Number Six's flat where he is calmly listening to music. His passive denials aggravate Number Fourteen, who attacks him. After a brief struggle, Number Six throws him out the window.
Ready for the final step, Number Six goes to the Green Dome to find Number Two cowering in his chair, isolated. Number Two accuses Number Six of being a plant, filing secret reports. Number Six neither confirms nor denies but asks what Number Two should have done if he believed that. Number Two admits he should have cooperated and Number Six accuses him of being a bungler, of interfering with an investigation. He says that the authorities don't like failure, and Number Two has failed them. Number Two begs Number Six not to report him and Number Six agrees... but says he'll have to report himself. Now a broken man, Number Two calls his superiors and informs them they need a replacement.