Reese and Finch learn that their new Numbers are the five Dons of New York City, and figure that Elias is making his move for complete control of organized crime.
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.
While Carter tries to determine if her boyfriend is working with HR or not, Finch infiltrates a tech corporation to determine if their new Number is trying to help the company or hurt it.
Reese and Finch must protect Judge Samuel Gates, who wants nothing to do with their extralegal activities even though his refusal could cost him his life.
Reese and Finch become day-care providers when the Machine gives them the number of a six-month-old baby. Meanwhile, Carter begins to question her alliance with the two men when Elias shows up.
While Carter tries to maintain her cover as an FBI temporary agent while helping Reese, Fusco has to protect a new Number on his own while Reese ducks some old enemies from the past.
Reese and Finch go into overtime when the Machine gives them the numbers of four Persons of Interest. Meanwhile, Carter deals with the aftermath of the recent assassination attempt on her, and Reese's past resurfaces.
When Carter meets with Reese for the first time, he asks her to help him with their newest Number: a young lawyer from the wrong side of the tracks whose life is threatened.
Reese, Finch, and Fusco must protect Detective Carter without giving away their true identities, when the Machine gives them her name as the next Person of Interest.
The Machine gives up the number of Dr. Megan Tillman, a promising young physician, and Reese undertakes 24-hour surveillance of the doctor to determine the threat against her. Meanwhile, Fusco runs afoul of the Torero Cartel when they come looking for the drug money that his former partners stole from them.moreless
Reese and Finch head off to a small coastal town when The Machine gives them the Numbers of six missing people. When a storm moves in, they are trapped at a police station with several locals... and one of them is a killer.
Reese works as a driver for the newest Person of Interest: an attractive woman who is a master of shady deals. Meanwhile, Carter investigates a murder connected to the stolen evidence box for the M. Elias case.
The Machine becomes increasingly erratic because of the computer virus, and Reese and Finch must find an elusive tech millionaire. Meawhile, Carter puts herself at risk when she tries to find Cal's killer.
The team's newest Person of Interest is a teen genius and Finch goes undercover as a substitute teacher to protect him. Meanwhile, Carter takes on her first assignment as a temp agent for the FBI.
Reese and Finch attempt to protect Mira, a hotel maid with a long list of enemies. Meanwhile, Carter gets a job offer due to her help in the "man in the suit" case.
To combat Root and Decima, Reese and Finch must seek out unusual allies to save The Machine. Meanwhile, HR prepares to eliminate Carter when she probes into Cal's death. And in the past, the final fate of Nathan is revealed.
A mysterious millionaire, Finch, approaches John Reese, a CIA field officer who is believed dead, and offers him the chance to stop violent crimes before they happen. Finch can predict the person involved, but not how or where they are involved. In his first assignment, Reese must help a district attorney who Finch has predicted will be involved in a violent crime.
Reese and Finch try to help a billionaire tech magnate only to discover that doing so may compromise their existence when he sets out to find out who they really are and what they know.
While Carter deals with corruption within her own department, Reese and Finch help an elderly gambler and try to figure out why the mob wants him dead.
The newest Number is a famous cardiologist, but by the time Reese gets to the man, it's too late: he's already been given a slow-acting irreversible poison. While Reese and the doctor try to track down the man who poisoned him, Carter has a tough decision to make when IAB moves in on Fusco for the murder of his partner a year ago.
While Reese and Finch look after their newest Person of Interest, a teenager whose brother was recently murdered, Finch worries that his dead partner's son Will is getting too close to learning the truth about the Machine.
Reese's former partner Kara abducts him as part of her scheme to unleash a wave of cyber-terrorism across the world and get revenge on the people she believes wronged her.
In order to save a former Marine who needs money to pay off a personal debt, Reese must infiltrate a gang of ex-soldiers working as robbers. Meanwhile, Carter draws closer to Reese and realizes that he's not the cold-blooded killer that she's suspected.
The new Person of Interest is a young trader who has become involved in a multi-million dollar financial scam, and Reese has to pose as a wealthy investor to watch their client.
Reese and Finch must track a cab driver whose Number has come up... but they don't know if he's involved or if one of his passengers may be the intended victim or predator. Meanwhile, Simmons continues to put pressure on Fusco.
Reese and Finch set out to protect a surgeon who has come up as their newest Person of Interest. However, when they discover that someone from Reese's past is involved, they turn to a former Number for help.
When the Machine turns up a deceased individual as a person of interest, Finch must remember how he came to create the machine and determine how the apparent error could have occurred.
Reese and Finch must hunt down their newest Person of Interest, a man with Cold War espionage who disappeared over two decades ago and has returned to the U.S. for some unfinished business.