Samaritan makes one last desperate attempt to preserve itself from Finch's virus, and the team go on what may be a suicide mission to stop it.
Finch breaks into the NSA to plan the virus that will destroy Samaritan... and the Machine. The only ones who can get him out alive are Reese, Sameen, and the Machine, if they can get to him in time. Meanwhile, the Machine shows Finch simulations of what the world would have been like without it.moreless
The President is tapped as the next Person of Interest, and the team finds itself receiving some unexpected help. Meanwhile, Finch goes on a roadtrip with the Machine to begin his final campaign against Samaritan.moreless
After Finch goes to the wrong place at the wrong time, Samaritan gets a fix on him and won't stop until it captures him. The team rallies to protect their friend... but not everyone will come out alive.moreless
The Voice uses a hapless locksmith to plant a bomb in an investment firm, in the first step of a new plan. Meanwhile, Sameen makes her way to New York and Root finds her.moreless
Reese and Finch are trapped in a hospital ER when a superflu breaks out... and they realize that Samaritan is responsible. Meanwhile, Fusco continues his own investigation, while Sameen stages another escape.
While Root protects a radio host who has tapped into Samaritan's secret communication system, the Machine instructs her in how to use it to contact Sameen. Meanwhile, Samaritan keeps chipping away at Sameen's resolve, and Fusco realizes that Finch and Reese will never trust him with the truth.moreless
The team's new assignment is protecting a couple on the day of their wedding. Someone wants to stop the wedding... or do they? Meanwhile, Fusco crosses paths with Bruce when the two of them investigate the new player in town, each unaware that it's Samaritan.moreless
Samaritan is connected to the newest Number: a sound analyst who is looking into the death of a high school classmate. Meanwhile, Elias' friend Bruce demands answers concerning who murdered the crime boss.moreless
Sameen escapes her captors and reunites with her teammates, but they soon realize that their friend may not be as free as she believes.
The team's newest Number has ties to the CIA, endangering Reese's cover when he's forced to intervene.
While Reese and Fusco deal with a backlog of Numbers, the Machine starts giving out false Numbers after its recent reboot. Worse, it flags three of the team members as threats due to their violent histories, and locks Finch and Root out of the system.moreless
Reese and Finch try to get the case containing the Machine's damaged code to the station so that they can decompress it. Meanwhile, Fusco deals with the aftermath of Dominic and Elias' shootings, while Root tries to dodge Decima's agents without the Machine's help.moreless
As Finch and Root go on a seemingly random series of errands to save the Machine against Samaritan's onslaught, Dominic threatens to shoot Harper and Elias unless Reese puts him in contact with Finch.moreless
The Machine sends the team two new Numbers: Elias and Dominic. Meanwhile, Finch and Root get a clue to Sam's whereabouts, and Control tries to learn the truth about Samaritan.
Reese sets himself to solve a case that Carter was never able to close.
Reese and Finch try to protect a software CEO whose behavior becomes erratic after a hacker attack reveals his secrets.
The team's new Number is Frankie Wells, a bounty hunter who refuses to give up on a target despite the threat to her life. Meanwhile, Finch links back up with Beth Bridges.
The team's new Number is a psychologist whose unorthodox technique for helping his patients find closure puts him at risk. Meanwhile, in the past Finch tries to deal with the trauma of losing his best friend Nathan.moreless
Reese and Finch protect a street-savvy grifter who makes the mistake of stealing laundered money from Dominic. Meanwhile, Root infiltrates a software app company on the Machine's behalf.
Reese and Fusco help a transcriber at a software firm who is the team's new Number, while Claire contacts Finch and asks him for help against Decima.
Finch suspects that a fellow juror is trying to rig the proceedings in a murder trial. Meanwhile, Reese begins to open up to the department's therapist.
While Reese and Root look for Sam in an upstate New York town, Fusco helps out the newest Number with the help of a previous one.
Samaritan begins to withhold information from the ISA, raising Control's suspicions. Meanwhile, Root and Reese search for their missing teammate.
The team must go on a seeming suicide run to prevent the financial meldown that Samaritan has engineered.
To demonstrate its power to the Machine, Samaritan launches a massive effort to shut down all crime in NYC for 24 hours... and then unleash it worse than ever. Meanwhile, Finch and Reese try to keep up with the new influx of Numbers, and Root meets with her opposite number.moreless
Reese and Finch receive a new Number: Elias, who Dominic wants dead. Meanwhile, Root rescues Sam from Martine but Sam doesn't want to be rescued, and threatens to go public if they don't let her help save Elias.moreless
The team's new number is a police academy recruit: a loose cannon who is apparently working for the gangs. Meanwhile, Samaritan sends Martine to track down the woman who prevented it from obtaining the virus.moreless
The team's new Number turns out to be an international jewel thief, and Sam has to get close to the man to find out if he's victim or perpetrator. Meanwhile, Finch recruits Root to help him undermine Samaritan's plans to distribute tablets to school children.moreless
The team's new Number is a mild-mannered insurance agent who is pretending to be a police detective to investigate the supposed suicide of a co-worker's brother. Meanwhile, Finch is sent to a conference in Hong Kong and meets an attractive businesswoman specializing in computers.moreless