With Finch missing -- kidnapped in last season's finale cliffhanger -- Reese enlists Detectives Carter and Fusco to join the search for his friend.
With the Machine's help, Reese closes in on finding Finch as he uncovers shocking details of Root's past. Delivering the number of a cold case, The Machine leads Reese ever closer to catching up with Finch and his kidnapper.
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.
Is a killer's life worth saving? When The Machine gives Reese and Finch the number of a mob enforcer whose life becomes endangered, they must decide whether to intervene or allow karma to balance the scales of justice. Meanwhile, Finch seeks aid from an unlikely source.
Bury the Lede
Reese must protect an investigative journalist without her knowing it or risk becoming part of her story.
The High Road
Reese is out of his element when The Machine's latest number sends him to the suburbs, forcing him to play house and go undercover in an idyllic neighborhood.
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 person of interest, forcing them to turn to an unlikely source for help.
The team find themselves spread thin when the numbers come up for both a husband, Daniel Drake and his wife, Sabrina. Will it be "til death do us part?"
Finch and Reese's surveillance skills are pushed to the limit when a New York City cab driver's number comes up and any one of his passengers could be involved in the impending crime. Hundreds of passengers add up to hundreds of suspects.
While the FBI refocuses their efforts to catch "The Man in the Suit," Reese's latest POI becomes a personal quest after he learns that she's the sister of a soldier who was killed in action.
Finch goes undercover as a high school substitute teacher to protect a teenage genius who reminds him of his own adolescence as a child prodigy, while Carter undertakes a dangerous mission to stop the FBI from discovering that an imprisoned Reese is the "Man in a Suit."
While Carter plays a dangerous game by engaging in mental warfare with the FBI to help Reese evade Agent Donnelly's narrowing focus, Reese crosses paths with foes both old and new. Meanwhile, Det. Fusco is forced to fly solo to save the team's newest POI: supermodel Karolina Kurkova.
Has Reese become the latest Person of Interest? Caught in the crosshairs of a former acquaintance orchestrating a massive act of cyber-terrorism, Reese is abducted. Now, the team must race to save his life before it's too late.
Reese and Finch meet their match in a tech billionaire POI whose curiosity and limitless resources threaten to expose their identities and sabotage their efforts to save his life.
Reese and Finch race to save the life of a hotel maid, Mira Dobrica, but find themselves surrounded by more suspects than they may be able to eliminate when they realize that any guest or staff member could be her potential killer. Meanwhile, Detective Carter weighs a major offer from the FBI.
Reese's counterpart, lethal and sexy government operative Samantha Shaw, 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 ever when they discover that her remarkably elusive skills equal their own.
After the machine gives Reese and Finch six numbers at once, their search for clues lead them to a coastal town where they are forced to ride out a storm with a group of locals in a police station. However, as the weather rages outside, a sinister situation arises inside when they realize there is an unidentified killer hiding among them.
When an elderly card sharp's number comes up, Reese and Finch travel to Atlantic City to delve beneath the surface of their POI's seemingly ordinary life for answers. In New York, Carter's crusade to clear a fellow detective's name brings her perilously close to identifying the remaining HR faction within the department.
When the number of a leading tech executive comes up, Finch infiltrates her corporation to gather intel -- but can't determine whether she is working in her company's best interest or planning to destroy it from the inside. Meanwhile, Carter continues to question Detective Beecher's integrity after he provides incriminating information about a fellow detective.
When a luminary in the world of medicine is poisoned, Reese and Finch have just 24 hours to determine the deadly toxin he was given and find the person behind the attack. Meanwhile, Detective Fusco's corrupt past catches up with him when an informant gives the Internal Affairs Bureau the crucial information they need to send him to prison.
Reese and Finch realize that a virus has rendered The Machine erratic, causing it to issue numbers irregularly. As they race against the viral countdown, the team searches for a tech millionaire so elusive no one has ever seen him. Also, Detective Carter's mission to bring Cal Beecher's murderer to justice lands her squarely within the sights of the HR criminal organization.
Reese and Finch team up with some surprising allies in a race to save The Machine from a familiar, nefarious entity; and the true nature of Finch's relationship with former partner Nathan Ingram is revealed. Meanwhile, Carter tries to bring Beecher's murderer to justice and finds herself at odds with the criminal organization HR.
It's Fleet Week in New York City, making the hunt for one Naval Officer among a sea of sailors even more difficult for Reese, Finch and Shaw.
Nothing to Hide
The number comes up for an Internet data broker in the business of eliminating people's privacy, but finds his own being rapidly stripped away. Reese tries to protect him as his life is being dismantled by an unknown assailant and spiraling out of control, while Finch calls on Shaw, Carter and Fusco for help in finding whoever is after him. Meanwhile, the demoted and uniformed Carter finds herself unexpectedly paired with her new rookie partner, Mike Laskey.
Reese and Finch enlist the help of Carter, Shaw and Zoe Morgan, who use their feminine wiles to bait a chameleon playboy who is either a predator or someone else's imminent prey. Meanwhile, The Machine helps Root to plot an escape from her psych ward confinement before a dangerous enemy can track her down.
The Machine issues the number of a prominent New York lawyer whose husband was recently murdered, and the team has to quickly determine whether she orchestrated the death, or if she is being framed. Meanwhile, Carter faces an issue with her new partner, Mike Laskey, after he spots her with Reese aka "The Man in the Suit."
When Shaw is tasked to stay close to a 10-year-old identified by The Machine, she grudgingly develops respect for the young girl's skills in surveillance and realizes it could be the very reason why the girl's number has come up. Meanwhile, Carter's mission to bring the criminal organization HR to justice risks exposure.
Freed from her psych ward confinement, Root receives a directive from The Machine that requires Shaw's assistance -- by any means necessary -- and takes extreme measures to gain her compliance. Also, Reese and Finch look for clues as to why a mild-mannered estate investigator's number has come up.
The Perfect Mark
When The Machine issues the number of a hypnotherapist, the POI team discovers that he is more than just a master of the mind. Meanwhile, Carter tracks down an antiques dealer whose business is connected to the criminal HR organization.
The POI team's war with HR nears a boiling point when Finch receives 38 numbers at once from The Machine. He discovers they are connected to an unknown player who is inciting an all-out war between the crime organization and the Russian mob. Meanwhile, a window into Carter's past is seen through flashbacks with her son's father.
Danger closes in when the epic battle to bring the criminal organization HR to justice reaches new heights. And when the Machine suddenly gives out Reese's number, the POI team faces their greatest threat yet.
The Devil's Share
As the POI team seeks justice for one of its own, Finch realizes one of his team members may go one step too far, in order to end the war with HR. When The Machine singles out one of criminal organization HR's key players, the number may be up for corrupt NYPD Officer Patrick Simmons.
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.
Just when Reese thinks he's out, The Machine pulls him back in. Boarding an international flight in an attempt to put the team and the past behind him, Reese is angered when he realizes his travel plans have been manipulated and The Machine has other plans for him.
Reese rejoins Finch in New York, but a daring plan could make his first mission back the team's last. When the team receives the number of a highly skilled antiquities thief, a surprising turn of events finds them planning a high-stakes heist which could land them all in jail.
Finch goes undercover in an emergency call center to protect a 911 operator in a state of emergency, but it soon becomes clear that the threat reaches further than the team could have anticipated.
How did Finch operate before the Man in the Suit? The secrets of his 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.
Most Likely To...
Reese and Shaw infiltrate their most dangerous location yet - a high school reunion, posing as alumnae in order to keep eyes on the latest POI, Matthew Reed. 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 - by threatening his former fiancée and love of his life, Grace Hendricks - in an attempt to lure him out of hiding.
A House Divided
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.
Deus Ex Machina
The team takes desperate actions 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.
The team must devise new ways to continue their work without being detected by Samaritan after they're forced to take on new identities.
Although Finch insists that he no longer wishes to help with new numbers, his interest is piqued when Reese learns that the newest POI is a brilliant college student engaged in a mysterious, life-and-death scavenger hunt. Now he must decide if he can help without alerting Samaritan.
Finch recruits Fusco to stay close to the latest POI, a professional "wingman" whose number has come up, but learning how to approach women soon becomes the least of his worries. Meanwhile, Reese must find a way to play by the rules at his new day job as the Machine sends Finch and Root on a mysterious errand.
Reese's cover job as an NYPD detective becomes complicated when the young brother and sister he's protecting become targets of a gang investigation.
Finch is suspicious when a gifted political pollster's number comes up at the same time that his typically ironclad predictions go wrong - and believes that the two events are linked. Meanwhile, Reese is sidelined by a direct order from Captain Moreno.
Reese, Shaw and Fusco must protect an unassuming office worker who stumbles into a dangerous conspiracy while moonlighting as a fake detective. Meanwhile, Finch travels to Hong Kong as part of his academic cover identity.
Honor Among Thieves
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. Finch and Root, meanwhile, undertake a dangerous sabotage mission.
Point of Origin
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.
The Devil You Know
Reese and Finch are caught in a power struggle for control of the city's gangs when Elias is targeted by Dominic, the ambitious leader of the Brotherhood. Meanwhile, Root and Shaw disagree over how to handle a new threat from Samaritan.
The Cold War
Samaritan demonstrates its true power by taking control of New York for 48 hours and erasing crime from the city in an attempt to lure The Machine out of hiding.
If - Then - Else
Samaritan launches a cyber-attack on the stock exchange, forcing the team to risk their lives in a desperate mission to stop a global catastrophe.
Control - Alt - Delete
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.
Reese and Root's hunt for Shaw takes them to a small town in upstate New York where it becomes apparent that not everything is as idyllic as it seems. Also, Fusco teams with a former POI to tackle the newest number.
When the Machine arranged 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 who Finch tired to protect from Samaritan, reaches out to him for help.
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. How many enemies can one person make?
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 tries to protect a bounty hunter who refuses to let the potential threat to her life deter her from the relentless pursuit of her target. Also, Finch tries to set the plan in motion that he began in Hong Kong.
Search & Destroy
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 perilous personal journey when he takes it upon himself to honor Detective Carter's memory by attempting to solve a cold homicide case she 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 its AI rival, 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 what is left of The Machine, while Root fights for her life and Fusco is questioned by the NYPD.
The Machine experiences a glitch upon 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 their past violent behavior.
Truth Be Told
Reese's cover could be blown when he realizes that the latest POI has a connection to his old colleagues in the CIA.
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, Fusco is threatened by an ally of Elias, who is looking to avenge his friend's death.
A More Perfect Union
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 may have stumbled on information that someone is willing to kill to keep secret. 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 which has just become 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, trapping Reese and Fusco in their own precinct with several armed gang members and the latest POI. Also, Root makes a shocking discovery.
The Day the World Went Away
Finch's number comes up when a fatal error blows his cover identity and sets off a 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.
The POI Team - Finch, Reese, Fusco and Shaw - embark on one final mission to prevent Samaritan from destroying The Machine and cementing its hold over mankind.