Nathan Ingram comes to see Finch as he works to prepare the Machine for turnover to the government. Ingram assures his partner that they’ll be fine for one more night. He admits that he’s glad to be rid of it given the number of dangerous individuals that it discards simply because they’re not terrorists. When Finch says that they had to draw the line somewhere, Nathan points out that he has no one in his life to care about. After a moment he apologizes and suggests that after seven years, it’s time for Finch to find someone. Finch hints that he has but his partner doesn’t believe it.
Reese follows Finch across town and gets a call from Fusco. He tells Reese that Simons wants him to meet some of the top men in HR next week, and Reese tells him to call him then because he’s busy now. As Fusco hangs up, he notices Carter watching him... unaware that she has files on the HR officers.
Finch gets a phone call and goes to a pay phone to answer it. He simply listens and then calls Reese and says that they’ve received another Number. As Finch moves off, Reese looks around, wondering who called his boss and how they found him near the payphone.
Theodore Gibbons calls Henry Peck and thanks him for spotting a suspect.
At the library, Finch tells Reese about Henry, who picks stocks for a small financial firm. Henry maintains security on himself, making it difficult for Finch to hack his voicemail. Reese asks how Finch got the Number and demands to know how the Machine communicates with him. When Finch wonders why, Reese points out that he would need someone to carry on if something happens to him. Finch says that he has a contingency in place but Reese insists that he’ll have to reveal the secret sometime.
Reese runs surveillance on Henry at his office, while Finch confirms that the company’s firewall is impenetrable. Henry leaves work and Reese passes by, planting a bug on him. Meanwhile, Henry calls Alicia, a name that he’s never heard of. His co-worker arrives and Henry admits that he wipes his phone memory every day. Since the building is impenetrable to outside signals, Reese goes in behind Henry and claims that he’s meeting with a CFA. Henry goes through a secure door and Finch loses the signal, and the receptionist tells Reese that he’s not scheduled and she can’t let him go back. Reese notices her holding a gun under her dock and quickly leaves, and tells Finch that they’re dealing with a secret governmental information facility. He figures Henry is some kind of spy and they wonder how to spy on a spy.
Finch goes in posing as a technician, hides a camera and transceiver in a new coffeemaker, and wires it directly into the building’s electrical system. Reese watches from the van as Henry, an intelligence analyst, explains how he tracked a terrorist. When Finch gets there, he confirms that the building is a NSA listening station.
Henry goes home that night and Reese watches him. However, the analyst has no family or friends and works around the clock. The landlord calls the police with a complaint and they inform him that the landlord came in to fix a smoke alarm and found drugs. Henry insists that they’re not his but they take him down to the station. Reese gets feedback from the bug and Finch confirms that there’s another bug, meaning someone else is listening in. The listener leaves the building and Reese follows him, but loses him in traffic. Reese tells Finch that he figures Henry has been set up and wonders why.
The next day at the library, Reese looks around for clues about Finch and calls Carter. She tells him that Henry made bail an hour ago. He only has a speeding ticket on his record, and he fought to get it off by sending a 78-page brief to the judge. Once Carter hangs up, Finch comes in and explains that he checked a nearby security camera. It shows the same guy Reese saw, entering Henry’s apartment building. Reese goes to keep an eye on Henry.
Henry is at the office when his superior tells him that due to the arrest, he’s being placed on administrative leave and his security clearance is suspended. His superior doesn’t believe his claims that he’s being set up, and warns that if he files his complaints then Henry might seem unstable. Reese watches and figures Henry is being forced off, and Finch wants to know why. On the street, Henry tries to call Ted Gibbons, the Deputy Director of the NSA, but the man refuses to take his calls. Reese and Finch figure that whatever Henry is into his big and that he asked questions about the wrong thing.
As Henry goes into his apartment, Reese sees the damaged security camera that was working the previous night and realizes that someone is in Henry’s apartment. When Henry enters his apartment, he finds pills scattered on the floor and a whiskey bottle on the table. The man from the previous night grabs Henry as Reese bursts in, and the two men struggle. The intruder manages to escape and Reese tells Finch that they’re dealing with a government-trained assassin.
Henry has run off and Finch takes to the streets to track down the bug that Reese planted on him earlier. Meanwhile, Henry gets through to Gibbons using his daughter’s cell phone and reminds him that Gibbons called him off-the-record three weeks ago to thank him for a report on a man named Carlson. He didn’t put Carlson’s name in the report, and Carlson was the key to stopping a terrorist attack. Gibbons tells him not to call him again and hangs up. Reese catches up to Finch, who tells Reese that they want Henry dead because he’s been asking about the Machine.
Nathan meets with Alicia Corwin at a bar and tells her how his company will ship the Machine to the government. She assures him that their facility for it is secure, and that the Machine will send a suspect name to the proper authorities via untraceable means. Nathan agrees, noting that only eight people know it exists. Alicia says that there are only seven and he tries to cover up his slip of the tongue. He then asks if the people at her end can be trusted, and she says that they’ll take care of it. Nathan realizes that something has her rattled, but she insists that she’s fine but will be happy when she’s done with the Machine.
Carter calls Reese to warn him that someone saw him fighting at Henry’s. Finch cuts off the call, insisting everything is fine, but she isn’t convinced. Meanwhile, Reese and Finch continues to follow Henry, and Reese asks what is going on. Finch explains that the Machine isn’t legal, and that the people he entrusted it to are more ruthless than he anticipated. Henry gets a call from Alicia, and Reese realizes that it’s Alicia Corwin. Henry tells her that his report went through her office but it’s been shut down for a year. Alicia says, a single word, “sibilance,” and tells him to run. As he takes off, Finch tells Reese that they need to stop Henry before he learns anything else. If he talks to anyone else, the government will eliminate them as well. If they are known to get involved, the government could trace them back. Reese is more concerned by the fact that he has discovered Henry ditched the bug.
That night at the library, Reese confirms that Henry closed out his bank accounts and handed out his credit cards to the homeless. He figures the government has a put an elite three-man team on it, a team that handles black-ops. Reese figures they’ll Henry the same way that he would, looking for cash-only hotels with Internet access.
The lead killer, codename Pennsylvania Two, calls their superior and admits that they failed to kill Henry. The killer warns that Henry has help, and his employer tells him to do whatever it takes to kill Henry.
Finch gets a hit on a youth hostel and has confirmed that Henry hacked the card reader at his office. He figures that Henry is going in to get evidence to clear his name.
Henry breaks into the building and Reese goes in after him. Finch tells him to avoid direct contact. However, the black-ops team opens fire and Reese tackles Henry, getting him out of the line of fire. Henry runs outside and throws a bottle at a passing police car. He has the papers he obtained from the office and tells them to keep them safe, and the officers arrest him. Reese comes out and sees them drive away.
Finch is finishing the Machine shutdown when Nathan arrives to tell him everything is in place and it will take ten days to move the Machine. As Finch prepares to shut it down, Nathan asks if they have a contingency and wonders what they do if the government abuses the Machine. Finch reminds him that the Machine is coded to upgrade and patch itself. He insists that no one else can alter it, but Nathan doesn’t believe it and says they should put in a backdoor off-switch. Finch warns him that the tiniest exploit could be abused if someone else found out about it. He says that they need to trust the Machine that they built and let it go, and initiates system shutdown. Once it’s done, Finch leaves the building.
Carter has Henry rerouted to her station. Fusco meets with him and he explains that he found six reports that he wrote, and each one had a name inserted into it. Each name was the key player in stopping a terrorist attack, and the only way someone could be that accurate was by using illegal surveillance on a massive scale. “Sibilance” is an internal audit of the NSA intranet that uncovered massive amounts of data being covertly sent out. It would take a huge organization to scan through all of that data, and Henry realizes that it would take a computer and they actually built it. He reviews how the government wanted a machine that could catch terrorist before they strike, and Henry figures that someone succeeded in building it.
Once Henry is done, Fusco steps out and Carter wonders why he’s been talking to her suspect. Fusco dismisses his testimony as the ravings of an insane man, unaware that Reese is in the office disguised as a police officer. He goes to the interrogation room and gets Henry out of the building, stealing a taxi cab. Finch tells Reese that they have to destroy all of Henry’s evidence and make sure he doesn’t find anything else. Henry calls the Office of Special Counsel before Reese can stop him, and Finch warns Reese that one of the people who knows about the Machine works for the OSC. Reese tells Henry that no one is safe.
The black-ops supervisor gets a trace from the phone call and directs them to their target. Another of the soldiers, Fox, opens fire, takes out the cab, and moves in. Reese fights back and manages to stab Fox with his own knife. However, Reese discovers that Henry has slipped away in the confusion. He figures that Henry won’t give up and Finch agrees. However, he warns Reese that the people know about the Machine won’t give up, either. However, he explains that a friend showed him how to do the right thing even when faced with an intractable problem.
Nathan goes back and turns on the Machine, and then programs it with a contingency program.
Henry arranges a meeting with a reporter, unaware that the government people know about it. Finch meets with Henry right now and tells him that Reese is dealing with the assassins sent to kill him and the reporter. He then says that the Machine exists and tells him to stop asking the question. When Henry asks him where it is, Finch says that he understands but advises him not to try and solve the mystery. He says that when he tried to solve it, it cost him something he values more than his own life. Finch gives him new identity papers and money and advises him to leave. When Henry wonders how he knows everything about it, Finch says that he built it and walks away.
At the station, Det. Tierney tells Carter that they pulled Henry’s prints off of a burnt-out cab. Fusco listens in as Tierney gives her what few papers survived the crash. One of them has the word “Sibilance” on it. Fusco then calls Reese and tells him that he meets HR in three days. Reese says that he’ll be ready and that the next time he sees Fusco, he might have Finch’s address.
Reese hangs up and gets tea from the same street vendor that Finch orders his from, having traced the paper cups he uses. A truck with the magazines that Finch reads pulls up to a nearby apartment and Reese knocks at the door. A woman, Grace, answers the door and Reese, posing as Detective Stills, says that someone reported a disturbance. He offers to bring in the magazines and she accepts, and Grace explains that she draws the covers so she gets extra copies. Reese notices a photo of her with Finch and asks who it is, and Grace says that it’s Harold, her fiancé. Harold found her when she was painting in the park, and offered her an ice cream cone in January. She explains that she lost Harold two years ago in an accident.
As Reese leaves, he finds Finch waiting down the street. He joins him and notes that he’s been watching the woman without being seen. Finch says that he has an app that warns him if he ever gets within a hundred yards of her, and explains that he isn’t good with people other than Grace. He didn’t realize what the government would do to control the Machine, and by the time he learned it was too late. All he could do was protect Grace by faking his death. Reese says he’s sorry, and Finch says that he was lucky to have four years of happiness.
Two Days Earlier
While Finch talks to Henry, they’re both unaware that Alicia is using a parabolic microphone to listen in.