A supercomputer developed by reclusive billionaire and software genius Harold Finch analyzes data patterns in surveillance for the U.S. government to identify impending acts of terrorism. But the computer, known only as "The Machine", can also identify ordinary people who are about to be involved in violent crimes. Can those crimes be stopped before they take place? Secretly tapping into The Machine, Finch and ex-CIA agent John Reese use vigilante tactics and state-of-the-art technology to identify the soon-to-be victims and prevent the crimes from occuring. Meanwhile, two NYPD detectives Joss Carter and Lionel Fusco are drawn into the cases and the mystery surrounding the two covert crime fighters.
In the series premiere, the social security number of a young prosecutor comes up. Now Reese and Finch must work together to figure out if their person of interest is the victim or perpetrator.
FINCH (Michael Emerson) gives REESE (Jim Caviezel) another social security number from the machine -- another chance to stop something terrible from happening. But there's something strange about this number. It belongs to Theresa Whitaker -- a teenage girl who was murdered two years ago. Finch claims his machine is never wrong. So why is it pointing them toward someone that it's too late to save? What does the machine know that they don't? With DETECTIVE CARTER (Taraji P. Henson) still hunting them down, Reese and Finch begin to find out what really happened to Theresa -- and discover that they might still have a chance to be there in time.
Reese goes undercover to find the threat surrounding the next person on Finch's list: a young army veteran named JOEY DURBAN (James Carpinello.) Fresh out of the service, Joey seems to be adjusting well to life back home. He has a good job, a beautiful girlfriend, and his whole life ahead of him. But Reese and Finch soon discover that even though Joey's off the battlefield, he's still putting himself in the line of fire. It seems Joey and his army buddies are using the skills they learned in combat to commit daring heists in New York. According to Finch's machine, Joey's about to kill or be killed -- so Reese infiltrates the group to find out which. With Detective Carter hot on his trail, Reese is closer to getting captured than ever before as he goes on a high-risk mission that puts his life -- and Finch's -- in danger.
When the number comes up on a promising young doctor, Megan Tillman (guest star LINDA CARDELLINI), Reese and Finch must unravel the threat while she's on-call and after hours.
Reese tracks a by-the-book judge whose number comes up as the Person of Interest. Unfortunately, Reese arrives at the judge’s house to get some background information and arrives in time to witness the judge’s son being kidnapped, but too late to stop it. Reese chooses to connect with the person of interest in order to gain his trust and help save his son. Turns out the kidnappers want the judge to manipulate a case he’s overseeing so the defense will win. Reese identifies the kidnappers as a group of Russian mobsters and spends his time searching for the son while Finch investigates the connection between the Russian mobsters and the defendant, a bank programming who is secretly launders money for the Russians and who killed a man while DUI. As time passes, the judge is forced into throwing the case; then he quietly sets up a time to go retrieve his son. Reese and Finch know the kidnappers plan on killing both the judge and his son and Reese must save them.
Reese fills in as the driver for Zoe, the Person of Interest. Zoe’s background is mysterious as she doesn’t have an employment record and lives in a very expensive apartment. As Reese takes her to a few calls, he figures out she’s a high-priced "fixer” who smoothes over problems for corporate clients as well as some public officials. She’s clearly a match for Reese and he’s very intrigued by her. After completing one assignment, there’s an attempt on her life. She retrieved a flash drive with a seemingly benign recording to the head of a drug company on the verge of launching a new migraine medication, and clearly the drug company doesn’t want the recording to get out. Reese and Zoe work together closely to figure out what the drug company is hiding; Finch also works on this problem by going undercover to meet with the head of the drug company and analyzing the recording. Turns out, the voice on the recording was a previous POI, before Finch had found Reese and taking down the drug company becomes very personal for Finch.
Finch gets the number belonging to CHARLIE BURTON (Enrico Colantoni), a high school history teacher in Brighton Beach, Brooklyn, and an unlucky witness to a Russian mafia murder. Reese, with no time to spare, rushes to Charlie's side and whisks him out of danger just as the mob descends on his apartment to silence him for good. But they can't shake the Russians that easily. In hot pursuit, the shooters chase them into the infamous Double B High Rises-- a city housing project that has fallen into disrepair and is now home to thugs and illegal enterprises. Reese must find a way to escape the Double B's with Charlie and get him safely across the river into Carter's hands so that Charlie can testify to what he saw and bring justice to the victim of the murder. But the mafia is dead set on killing Charlie and will stop at nothing to make sure that Charlie doesn't make it out of the Double B's alive. And when Reese loses contact with Finch, Finch must look to Detective Fusco for help.
Reese and Finch receive the number for WALLACE NEGEL (Alan Dale) -- a mysterious man who hasn't had a single electronic transaction in his name since 1989. But as they dig for more details, they begin to suspect that Negel is not who he seems. Reese knows a cover identity when he sees one. This man is a spy. When bodies start to turn up, Reese and Finch need to figure out how they are connected to this agent and why he has returned to New York City after so much time. In this game of spy vs. spy, the old school operator matches his spycraft against Reese and Finch's neo-technology. We also learn more about Reese's early days in the CIA and his relationship to a mysterious woman named STANTON (Annie Parisse).
Reese and Finch are put in a tough position when the Person of Interest turns out to be Carter. As they evaluate the current threats against her: an abusive husband whom Carter is watching closely; Elias, who is working with a corrupt element in the police department to get rid of her as soon as possible; and the perpetrator of her current murder case, who is threatened by how close Carter is getting to putting him away. Reese enlists Fusco's help to keep an eye on Carter, but both Finch and Reese worry that in order to save Carter, they risk being caught by her. As Reese manages to eliminate one threat after another, the hit comes from a very unexpected place. Carter gets shot, but a vest protects her and Reese eliminates the threat, giving Carter a new understanding of Reese.
The machine gives Finch 4 numbers almost simultaneously, which means the POI's are probably connected. When they find the first number murdered, Reese enlists Finch and Fusco to help keep the others safe. Unfortunately Finch isn't able to get there in time for the second victim. Reese figures out that the remaining two numbers are foster sisters and manages to rescue them from an attempt on their life. Finch determines that all four seemingly unconnected people met at the scene of a car accident and they did something to make them targets.
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.
Andrea Gutierrez is the person of interest; she's a feisty lawyer, who’s only had losing cases in her short career. Her current case is a lawsuit against the city to get an ex-con’s latest drug charges thrown out so he can regain custody of his young son. Reese manages to thwart one attack on Andrea’s life and put her out of harm’s way, but the person who wants her dead is persistent. As Finch, with Carter’s help, investigates Andrea’s background and current caseload, they uncover a huge conspiracy in DFS regarding its placement of children in foster care for money. Unfortunately, Andrea’s gets lured into a trap and Reese rushes to get there in time. Also, Finch meets up with the son of his deceased partner, Ingram. Will Ingram left his medical residency to work for Doctors Without Borders after his father’s untimely death. Though he inherited his father’s fortune, he has no idea about his father’s work and believes Finch is an insurance agent with no computer skills. Taking Finch’s advice to stay in town, he decides he’s going to connect with his father’s memory by investigating his life.
Reese and Finch's latest Person of Interest is a down-on-his-luck man (guest star MYK WATFORD) who may have reached his breaking point. As the case evolves, the duo calls upon a former POI for help, the resourceful and well-connected fixer Zoe (guest star PAIGE TURCO).
The Machine identifies Darren (guest star ASTRO), a teenager whose brother was just murdered, as the next POI. Now, Reese must struggle to protect the teen, who's hell bent on avenging his brother's death.
The latest number that the machine dispenses belongs to Michael Cahill, who on the surface is an unassuming and upstanding but solitary citizen, which masks the fact of being involved in a major smuggling ring led by a man named Vargas. Members of the ring will not hesitate to kill if anyone gets in their way. Reese quickly infiltrates the smuggling ring as one of their own. But when Reese follows Cahill away from the group, Reese finds that his former name is Daniel Tully, and that he is a husband, father and undercover cop, who is deep undercover. Cahill could have long ago put Vargas away, but is waiting to nab the ringleader, a man going by the code name L.O.S. Reese also learns that Vargas probably has a connection working inside the police force. While Finch gets Carter to provide information on the police workings of undercover cops, Reese get Fusco to re-establish his connections with the dirty cops to flush out Vargas' connection. If anything goes wrong, it could mean the demise of Cahill, Fusco or both. Seeing Cahill's conflict of his work against wanting to be with his family, Reese remembers back four years earlier on his return to the US and wanting to at least know what was going on with his ex-girlfriend Jessica.
With Finch putting up lucrative financial backing, Reese poses as a wealthy investor in order to get close to the person of interest, a wealthy and intelligent stock analyst who’s riding a wave of investment success. Finch does some background research on the analyst, Adam Saunders, and the only flaws on his record are his involvment in a Securities and Exchange Commission investigation into his firm and his secret romance with his boss, Sydney Baylor. However, no charges were ever filed against him and he appears to be making his money legally. Someone attempts a professional hit on Adam, but Reese saves his life and sends him into hiding in a nearby homeless encampment. Adam warns Reese that whoever is after him could be after Baylor as well, but they arrive at her apartment, they find that she's been murdered all the evidence points to Adam. On top of that, someone at the firm is engineering a massive short sell of stock, which could earn them millions while bankrupting thousands of the firm's investors. Finch hacks his way into Adam's company and is able to track the money he invested to the people responsible for the short sell; one of Adam's coworkers and a corrupt SEC agent. Finch and Adam mastermind and execute a plan to cut off the short-sell, get the investors' money back, and catch the bad guys. At the end of the episode, Reese intercepts a cell phone from Scarface that connects him to Elias.
As former crime boss Moretti leaves prison, his prodigal son, Elias sends a team to kidnap him. Fortunately Carter and Reese are there to rescue Moretti and take him to a safe house. Meanwhile, Finch is checking out their next POI, who turns out to be a five-month-old baby named Leila, given up at a safe haven hospital and no clue as to her parents’ identities. Finch notices two men clearly coming to take Leila away and he boldly decides to kidnap Leila himself. As Reese and Finch investigate Leila’s identity, they face the toughest challenge of their partnership, taking care of an infant. They track down Leila’s mother, only to discover she was killed in a fire 4 days earlier. They decide to place the Leila in her maternal grandparent’s care, but the baby is kidnapped by the same people who killed her mother. When they figure out the birth father’s wife is behind it all, they are shocked to learn they have no way of recovering the kidnapped baby. Reese decides to ask Elias for help. It’s a risky move, and Reese ends up having to trade Moretti’s location for the Leila’s safety. All ends well for Leila but Carter is furious with Reese and refuses to work with him again.
Finch and Reese are stymied to find their most recent POI is actually two different people. One is a beautiful woman who is an art dealer who is worried because she thinks someone is following her. The other is a man who was badly beaten and seems to be running an MDMA factory.
Elias goes after the heads of all the major mob families in New York, and Reese and Finch enlist Carter’s help to keep them all safe. When Elias learns of her involvement, he kidnaps her son and threatens to kill him.
The Machine's latest mark puts Reese undercover as part of an armored truck crew, a case that brings back memories of his last CIA mission and painful decisions he was forced to make.
It's Reese's birthday, and Finch gifts him with a day off - especially when he realizes that The Machine's latest number is sure to revive painful memories.
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.
When a psychologist's number comes up, Reese must protect her from one of her patients while eluding capture by the FBI, who are closing in fast. Meanwhile, Finch receives an unwelcome visit from an old acquaintance.