When the social security number of a young prosecutor comes up, Reese and Finch work together to figure out if their person of interest is the victim or perpetrator.

Reese and Finch question the machine's reliability when they are asked to investigate a teenager who was killed years earlier; Finch remembers the origin of the machine.

Reese goes undercover to find the threat surrounding the next person on Finch's list: a young army veteran named Joey Durban.

Reese and Finch get some help from Detective Fusco as they surveil their latest POI, Dr. Megan Tillman, while she’s on call and after hours to unravel the threat surrounding the promising young physician.

Reese and Finch have the added challenge of investigating a Person of Interest who wants nothing to do with their brand of vigilante justice.

Reese becomes romantically involved with the newest Person of Interest: an attractive woman who isn't all that she seems.

The Machine identifies a school teacher who witnessed a mob hit as their next POI and Reese and Finch rush to save his life.

When Reese and Finch discover that their latest POI has connections to Cold War Soviet espionage circles, they quickly learn how covert ops were handled in a world before The Machine.

Reese and Finch’s game of cat and mouse with Detective Carter becomes infinitely more complicated when The Machine declares that she is their newest POI.

As Detective Carter deals with the fallout from her recent encounter with Reese and Finch, The Machine ups the ante for the duo by giving them four Social Security numbers instead of one.

Reese is confined to a wheelchair recovering from his gunshot wound, but Finch sets him up in an apartment where he’s to keep an eye on the Super, who is their latest POI. Also, Finch approaches Carter and gives her a POI to show her what they do.

When Carter finally comes face-to-face with Reese, he urges her to join forces to help with their latest POI, a scrappy young woman from the wrong side of the tracks who turned her life around and became a lawyer.

The Machine gives Reese and Finch the number of a down-and-out man who has been pushed too far, and they're forced to turn to former Person of Interest, Zoe Morgan, for help.

The Machine identifies Darren, a teenager whose brother was just murdered, as the next POI. Meanwhile, Finch is growing concerned that the son of his former business partner is dangerously close to finding out about the Machine.

Reese discovers there’s more to the story after he infiltrates a smuggling ring to get close to his latest POI.

The Machine leads Reese and Finch to Wall Street when a sharp young trader at a major investment bank becomes embroiled in a multi-million dollar financial scam.

When The Machine spits out the number of a 6-month-old baby, Reese and Finch turn into overly protective parents – with an arsenal at their disposal. Meanwhile, when Elias resurfaces, Detective Carter begins to question her new allegiance with Reese and Finch

The Machine's latest number presents a unique challenge for Reese and Finch since the person has virtually no digital footprint - and appears to be leading a double life.

When The Machine spits out five numbers, naming the Don of each of New York’s crime families, Reese and Finch suspect Elias is planning to eliminate his competition.

Reese goes undercover as an armored car company employee, and faces memories from his past with the CIA.

Finch gives Reese his birthday off so that his partner doesn't have to face a Number that is tied to Reese's past.

The newest POI’s curiosity could spell his doom when he finds himself embroiled in a dark government conspiracy – one that Finch is all too familiar with. Meanwhile, Reese uncovers something revealing about Finch’s past.

As the clock ticks down, Reese winds up trapped with his POI in the most heavily surveilled part of the city, forced to rely on the help of Finch, Carter and Fusco to fend off the FBI, corrupt cops and a slew of old foes.

With Finch missing – kidnapped by his hacker nemesis, Root, Reese enlists Detectives Carter and Fusco to get his friend back, Meanwhile, The Machine never sleeps, disseminating a new number to Reese.

The Machine delivers the number of a cold case that leads Reese ever closer to catching up with Finch and his kidnapper, Root.

With Finch back in the Library, Reese returns to field work, only to face his toughest case yet – protecting the privileged daughter of a Brazilian diplomat.

When The Machine gives them the number of a mob enforcer whose life becomes endangered, Reese and Finch must decide whether to intervene or allow karma to balance the scales of justice. Meanwhile, Finch seeks aid from an unlikely source.

Reese must protect an investigative journalist through surreptitious means to avoid becoming part of her story.

Reese goes undercover in an idyllic neighborhood when The Machine’s latest number sends him to the suburbs.

The Machine gives Finch and Reese the number of a brilliant surgeon, but they soon discover that a resourceful third party has raised the stakes for this POI, forcing them to turn to an unlikely source for help.

The team is spread thin when a husband and wife’s numbers both come up

When the machine names a New York cabdriver as a person of interest, any of his passengers could be a part of the impending crime.

As the FBI pursues "the man in the suit," Reese is even more determined to protect the latest person of interest after learning she is the sister of a soldier who was killed in action.

Finch goes under cover to protect a youth who reminds him of himself; Carter goes on a dangerous mission for the FBI.

Carter tries to help Reese by engaging in mental warfare with the FBI; Reese has encounters with old and new enemies; Detective Fusco must protect supermodel Karolina Kurkova, the latest person of interest.

Reese is abducted by a former acquaintance planning a massive and potentially deadly act of cyber-warfare.

Finch and Reese meet their match: a tech billionaire whose curiosity and endless resources could expose their identities and ruin their efforts to save his life.

As Reese and Finch try to save a hotel maid's life, they encounter a litany of suspects; Detective Carter considers a significant offer from the FBI.

A lethal government operative who tracks and stops terrorist threats before they occur finds herself on the run – and the new focus of Reese and Finch's attention. However, their pursuit proves to be their most formidable when they discover that her remarkable skill set equals their own.

As Finch and Reese try to protect six people simultaneously, clues lead them to a coastal town; when a storm forces Finch and Reese to seek shelter in a police station with a group of locals, they realize a killer may be in their midst.

Finch and Reese head to Atlantic City to protect the latest person of interest, an elderly gambler; Carter tries to clear another detective's name.

Finch infiltrates a tech corporation to gather intel on an executive whose number has come up; Carter questions Beecher's integrity.

When a person of interest is poisoned, Finch and Reese only have 24 hours to identify the toxin and find the person responsible; Detective Fusco's past catches up to him.

When a virus causes the machine to malfunction, numbers are issued irregularly; the team searches for an extremely elusive tech millionaire.

Finch and Reese team up with unexpected allies as they race to fix the machine; as Detective Carter tries to apprehend Cal Beecher's murderer, she finds herself up against HR -- a criminal organization.

The Machine, now completely self-governed with its whereabouts unknown, resumes giving Finch its "irrelevant" numbers for people in danger, which include a U.S. naval officer in town for Fleet Week. However, with so many sailors flooding the streets of New York City, finding the officer in time presents an even bigger challenge for Reese and Shaw.

The number comes up for an Internet entrepreneur in the business of eliminating people's privacy, but finds his own being rapidly stripped away. As his life spirals out of control, Reese tries to protect him while Finch calls on Shaw, Carter and Fusco for help finding whoever is after him.

The team suspects the latest number to be a potential stalker/ killer. Root plots her escape from the institution and gives her psychiatrist a big surprise.

The team must figure out if a prominent lawyer orchestrated the murder of her husband or if she is being framed; Carter is spotted with Reese by her new partner.

Shaw must stay close to a 10-year-old girl with highly developed surveillance skills when she is identified by the machine; Carter's mission could be exposed.

After being freed from her confinement to the psych ward, Root needs Shaw's help with a directive from the machine; Finch and Reese look into a mild-mannered investigator.

The team is met with surprises during an investigation into a hypnotherapist; an antiquities dealer has ties to a crime organization.

The machine gives Finch 38 numbers at once; information about Carter's past is revealed.

The battle to bring a crime organization to justice reaches a new level; Reese's number comes up in the machine.

As the POI team seeks justice for Carter’s murder, Finch realizes one of his team members may go one step too far in order to end the war with HR. Also, The Machine gives out the number for NYPD Officer Patrick Simmons, one of the crime organization’s key players.

Flashbacks to Finch’s adolescence provide insight into his creation of The Machine. Also, the team receives the number of an already dying man, and Reese leaves the POI team behind in the aftermath of the war with the crime organization, HR.

Multiple enemies converge on the POI team as they protect a dying man whose number has come up. They struggle to keep their enemies at bay but without Reese, who has left them and their mission behind following the tragic war with HR, being down one man could have catastrophic repercussions for the team.

Reese boards an international flight in an attempt to put the team and the past behind him, but is angered when he realizes his travel plans have been manipulated.

Reese rejoins Finch in New York, but when the team receives the number of a highly skilled antiquities thief, a surprising turn of events finds them planning a heist which could land them all in jail.

Finch goes undercover in an emergency call center to protect a 911 operator, but it soon becomes clear that the threat reaches further than the team could have anticipated.

The secrets of Finch’s operation before he enlisted Reese are revealed, including shocking ties to present-day events.

The Machine assigns Root to seek out a janitor with a mysterious past, but when her very presence puts his life in danger, Finch also receives his number.

Finch and Reese must delve into the murky waters of international politics when they are given the number of a former government contractor who is stalking a UN diplomat. Also, an enemy attempts to gain an upper hand on Root.

Reese and Shaw pose as alumni at a high school reunion in order to keep eyes on the latest POI. Meanwhile, Finch and Fusco travel to Washington, D.C., to investigate the motivations behind Vigilance’s latest attack.

Reese poses as a Secret Service agent to get close to the latest POI, a U.S. congressman who may hold the key to derailing Decima’s plans to bring a second Machine online.

As Decima uses Samaritan’s feeds to hunt Reese and Shaw, Greer exploits Finch’s greatest weakness in an attempt to lure him out of hiding: his love for his former fiancée, Grace Hendricks.

When an unknown entity prevents The Machine from seeing the full picture of an impending catastrophic event, it sends the team five separate numbers to help them piece together the bigger picture. Meanwhile, Root’s team of hackers arrives in New York.

The team takes desperate action in its race to prevent the malevolent AI program Samaritan from coming online and making them its first targets. Meanwhile, the months-long battle with the anti-surveillance terrorist group Vigilance comes to a shocking conclusion.

Forced to take on new identities provided by Root, the team members try to adapt to their new lives. However, some find it hard to ignore The Machine's numbers, which puts them all at risk of being detected by Samaritan.

Despite not wanting to help with the new numbers, Finch's interest is piqued when the newest person of interest turns out to be a brilliant college student involved with a mysterious scavenger hunt.

Finch recruits Fusco to stick close to the latest POI, a professional 'wingman', but learning how to approach women soon becomes the least of his worries. Reese must find a way to play by the rules at his new day job. The Machine sends Finch and Root on a mysterious errand.

Reese's cover job as a detective at the NYPD becomes complicated when the young brother and sister he's protecting become targets of a gang investigation.

While Reese is forced to go to counseling for his violent tendencies, Root, Shaw and Finch try to help a new POI.

Reese, Shaw and Fusco must protect a unassuming office worker who stumbles into a dangerous conspiracy while moonlighting as fake detective. Finch travels to Hong Kong as part of his academic cover identity.

Shaw joins a team of international thieves in order to keep tabs on the latest POI, but an unexpected turn of events puts her in danger of being detected by Samaritan. Also, Finch and Root undertake a dangerous sabotage mission.

Reese volunteers as an NYPD police academy instructor in order to keep an eye on a talented young officer whose suspicious actions make him question her motives. Meanwhile, Martine – armed with information from Samaritan – hunts a member of the team.

Reese must save Elias from the Brotherhood. He can't get any help from Root or Shaw since Shaw's cover is blown and Root is escorting her to underground.

Samaritan shows its power by erasing crime from the city for a day in an attempt to force The Machine out of hiding.

Samaritan launches a cyber-attack on the stock exchange, forcing the team to risk their lives in a desperate mission to stop a global economic catastrophe.

Control, who oversees the handling of relevant numbers for the government, begins to question the methods and intentions of the Samaritan program. Also, alarming news reports of a pair of vigilantes rampaging through the Northeast begin to surface.

Root and Reese investigate a small town in upstate New York that holds the key to Shaw's location... and whether she's dead or alive.

When the Machine arranges for Finch to sit on the jury of a murder trial, he begins to suspect that a fellow juror is set to rig the proceedings. Meanwhile, Reese begins to open up to the department’s therapist.

Reese tries to protect a software programmer with a mysterious second life, but it’s unclear which side of her life the threat is coming from. Meanwhile, Claire, a young hacker whom Finch tried to protect from Samaritan, reaches out to him for aid.

Reese and Finch must protect Harper, a street-smart grifter, when her plan to steal cash from a medical marijuana dispensary goes up in smoke.

Reese and Finch try to protect a psychologist whose unorthodox methods for helping his patients find closure could cost him dearly. Meanwhile, flashbacks reveal Finch’s fragile state in the days following the bombing that killed his best friend, Nathan Ingram.

Reese must protect a bounty hunter who refuses to allow the potential threat to her life sway her from the relentless pursuit of her target. Also, Finch tries to set the plan he began in Shanghai in motion.

Reese and Finch scramble to protect a software CEO when his behavior becomes increasingly erratic following a hacker attack that reveals all his secrets and unravels his life.

Reese finds himself on a dangerous personal journey when he takes on a homicide case Detective Carter was never able to close.

Reese and Fusco get caught in the war between the two newest POIs, rival crime bosses Elias and Dominic. Also, a tantalizing clue to Shaw’s whereabouts leads Finch and Root into a possible trap, and Control goes rogue to uncover the true intentions of the Samaritan program.

Finch and Root race to save The Machine, which has been located by the rival AI, Samaritan. Also, Reese is caught in the middle of the final showdown between rival crime bosses Elias and Dominic.

Reese and Finch attempt to rescue the Machine’s source code before it deteriorates beyond repair. Also, Root fights for her life against an onslaught of Samaritan’s agents and Fusco is faced with hard questions following the deaths of Dominic and Elias.

The Machine experiences a glitch during rebooting, supplying Reese and Fusco with the numbers of dozens of people not actually involved in crimes, while also locking Finch and Root out after identifying them as threats based on past violent behavior.

Reese’s cover could be blown when he realizes the latest POI has ties to his old CIA colleague, Kara Stanton.

Shaw escapes her captors, but the team is unsure of her mental state when she begins to act paranoid and reckless.

Reese protects an NYPD analyst whose investigation into a software glitch has drawn the attention of Samaritan. Also, Reese and Fusco are threatened by an ally of Elias’s, who is looking to avenge his friend’s death.

The Machine sends Reese and Finch to a wedding to protect a pair of POIs before their nuptials. Also, Fusco becomes angry at being kept in the dark by the team and takes it upon himself to investigate a string of missing person reports.

Root goes undercover at a radio station to protect the host of a conspiracy theory show who stumbles upon information that could get him killed. Also, Samaritan’s agents try to convince a member of the team that their goals are noble.

Reese and Finch become trapped in a hospital that becomes ground zero for a deadly viral outbreak. Also, Samaritan’s newest recruit has second thoughts and Shaw continues to struggle with reality.

The mysterious criminal mastermind known as “The Voice” returns and traps Reese and Fusco in their own precinct with several armed gang members and the latest POI. Also, Root makes a shocking discovery.

Finch’s number comes up when a fatal error blows his cover identity and sets off a deadly series of escalating encounters with Samaritan’s operatives.

The team must unravel a conspiracy and stay ahead of the Secret Service when the President of the United States becomes their newest POI. Also, Finch separates himself from the team and considers taking drastic action to combat Samaritan.

As Reese and Shaw race to catch up with Finch, he infiltrates a maximum-security government facility in a desperate mission which could mean the end for not only Samaritan, but for himself and The Machine as well.

Finch, Reese, Fusco and Shaw embark on one last mission to prevent Samaritan from destroying The Machine and cementing its hold over mankind.