Presumed dead former CIA agent Reese and billionaire software genius Finch join forces as a vigilante crime-fighting team. Using a program that employs pattern recognition to determine individuals who will soon be involved in violent crimes, they are able to combine Reese's covert operations training and Finch's money to stop crimes before they happen. Academy Award nominee Taraji P. Henson also stars as NYPD homicide detective Carter, who becomes involved in Reese's investigations.
The team must decide whether to risk Samaritan detecting their new identities if they help an electronics expert whose son is being held by a drugs cartel.
Harold reluctantly agrees to help John protect a young woman who is participating in a deadly game, while Shaw works with a group of thieves as her new cover.
Fusco is assigned to a professional dating consultant who is soon to appear as a witness in a serious crime trial. Finch poses as a notorious arms trader.
Reese tries to protect a young brother and sister who have stolen a large sum of money from the notorious Brotherhood gang.
When a political pollster uncovers election rigging after his predictions go wrong, Samaritan sends an assassin to stop him from alerting the authorities.
Reese must protect a fake detective who has stumbled upon the activities of the Brotherhood. In Hong Kong, a tech company owner incites Finch's curiosity.
Shaw joins a group of international thieves led by the latest person of interest. Root and Finch are sent on a mission of sabotage.
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.
Shaw's cover is blown so Root is forced to escort her underground, forcing Reese to work alone to save Elias from the Brotherhood.
Samaritan tries to force the Machine out of hiding by taking complete control of New York for 48 hours. Greer's past as a MI6 field officer is revealed.
Samaritan launches a cyber-attack on the stock exchange, leaving the team with no choice but to embark on a 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.
The hunt for Shaw takes Root and Reese to a small town, where not everything is as idyllic as it seems. Fusco and a former person of interest team up.
While on a jury for a murder trial, Finch becomes suspicious of another juror. Reese starts to open up to a therapist.
Reese tries to protect a software programmer with a mysterious second life. Former person of interest Claire Mahoney appeals to Finch for help.
Reese and Finch must protect a street-smart grifter after her plan to steal cash from a medical marijuana dispensary fails.
Reese and Finch try to protect a psychologist whose unorthodox methods for helping his patients find closure could cost him dearly.
Reese must protect a bounty hunter who refuses to let a potential threat to her life stop her from hunting her brother's killer. Beth Bridges contacts Finch.
The CEO of a software company becomes the victim of a hacker attack that destroys his life. The Machine sends Root to retrieve a briefcase.
Memories of Carter resurface when Reese is badly wounded while trying to protect the latest person of interest, a suspect in one of her cold cases.
Reese and Fusco become caught up in the gang war between Elias and Dominic as it reaches crisis point. Finch and Root follow a clue to Shaw's whereabouts.
Finch and Root race to save The Machine, which has been located by the rival AI, Samaritan.