Characters: Person Of Interest Decima Technologies

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Decima Technologies is a private technology firm originally identified by Harold Finch as having developed a virus designed to infect the Machine. Decima is connected to a covert group in league with the Chinese to steal U.S. data, and is based in Shanghai. Finch discovers that only a small percentage of the data stolen goes to the Chinese, with the remainder going to another: an unknown recipient. The Office of Special Counsel is also aware of Decima. The organisation is responsible for the creation of Vigilance.

The only known leader of Decima is John Greer, identified by the Machine as the firm's Director of Operations.

They are responsible for the further development and unshackling of Samaritan, and now answer to it.

    In General 

In General

  • Bad Guys Do the Dirty Work: Decima was hired because they can be The Scapegoat if the government's surveillance activities get exposed again, but this no longer seems possible since Decima no longer exists as a business entity. Judging from how Greer contemplates eliminating Garrison after the latter reminds him of this part of their agreement, it's pretty likely that this was merely part of his ploy to get Samaritan the government feeds and that he has no intention of actually keeping it.
  • Batman Gambit: Terrifyingly good at pulling these off, due to a highly experienced former intelligence officer and artificial intelligence leading them, and it allows them a sizable edge over Team Machine who constantly tear through their assets in a straight fight.
  • Dragon with an Agenda: They're employed by China's Ministry of State Security, and share intelligence with them. However, they run their own operations independent from Chinese control. In the Season 3 episode"RAM", Greer doesn't mind having his employees launch an attack on an MSS facility in Mainland China to recover The Ordos Laptop. The operation leads to the entire facilities staff being slaughtered, something that would have probably annoyed the MSS greatly if they had realized who was responsible.
  • The Big Bad: Greer is the most visible representative of Decima but had unknown superiors who he reported to. Later this spot is taken by Samaritan
  • The Cracker: During "Trojan Horse", they shut out Harold from the Rylatech servers by taking control of his laptop, overheating its battery and cause it to explode. In the Season 3 episode "Allegiance", Greer has his people counter the Machine's surveillance capabilities when Root is hunting him through a New York subway station. They first kill the cameras, blinding the Machine. Then they take control of the stations loud speakers and increase feedback preventing the machine from tracking Greer via his foot steps.
    • Samaritan of all things is this. Season 4 has it compromising a disposable laptop Harold was using to hack into a computer system while in "The Cold War", it injects a virus into the NYSE computer systems to initiate a stock market crash
  • The Dragon: Jeremy Lambert, Greer's bodyguard and second in command along with Martine Rousseau, Samaritan's personal asset.
  • The Evil Genius: Greer and Samaritan are the resident ones at Decima Technologies. One's a former intelligence officer with half a century of experience in the field of espionage, the other is a Artificial Intelligence system which has been programmed to take over the world and has access to all computer systems worldwide.
  • Evil Brit: Their director of operations is one and the majority of his inner circle is made up of them.
  • The Men in Black: Employ mooks that look the part. Not as effective, though.
  • Names to Run Away from Really Fast/Meaningful Name/Punny Name: Decima Technologies
    • Also, Decima was the name of one of the Fates in Roman mythology. Specifically, the middle one, whose remit was choosing the patterns of every life. Yeah.
  • N.G.O. Superpower: As of the Season 3 "finale Deus Ex Machina", Decima achieved this status. They've basically been able to subvert an entire nation state through complex political manipulation, a False Flag Operation and with their own surveillance system being adopted by the US government, they're now in a position to influence US counter-terrorist efforts and use them to destroy those who oppose the company.
    • The Season 4 episode 'Prophets' reveals that they have begun to turn the American Political system into their plaything using Samaritan to conduct vote rigging, allowing 58 candidates of their choice to get into key positions of state level government nationwide, while their own human assets preserve operational security through killing anybody who realizes what's going on.
    • Even without Samaritan Decima is still a formidable adversary, with massive financial resources due to the profits made from selling intelligence to high paying clients, like the PRC Ministry Of State Security (along with implied use of their cyberwarfare capabilities to manipulate the stock market) and can afford to deploy well equipped assets during operations.
    • As of the Season 4 finale they've dropped all pretenses and liquidated a select group of people who threaten their goals, taking complete control over organizations such as the ISA
  • Nebulous Evil Organization: The show's most prominent.
  • Red Shirt Army: Unlike the Northern Lights hit squads, Decima Technologies mooks go down rapidly during their attempts to eliminate Team Machine during "God Mode". Occurs once again during the Season 3 episode "RAM" where among other screw ups, Kara swiftly shoots three of their operatives before they can get a round off during a hostage standoff.
    • Averted painfully with the introduction of their employee Martine Rousseau in Season 4. She is hooked up to Samaritan, allowing her to become omnipotent in combat. In the first demonstration of her capabilities she keeps up with Root. In the second, she keeps up with Shaw.
    • Her new unit isn't too shabby either, especially when they see action in the episode "If-Then-Else However, they only really do well in the simulations. When reality happens, Shaw kills and maims them with explosives, and finishes off the rest with Root using a barrage of gunfire.
  • Sharp-Dressed Man: Everyone at the company is this unless the need for a disguise requires them to put on other clothing.
  • Suicide Pact: Seems to have an arrangement with its operatives—if they are captured or compromised, and they kill themselves before they can be made to give up any intelligence, their families will be provided for. Examples: Martin in "Trojan Horse;" the Mook captured by Reese and Stanton in "RAM" who throws himself out a skyscraper window to avoid further interrogation. "A House Divided" confirms that it is company policy for the next of kin of any operatives lost in "accidents" to receive generous insurance payouts, while those who let themselves get captured get nothing.
    • Decima is dismantled between Season 3 and 4, so it is unknown if Samaritan's newer operatives still have the same arrangement.
  • Totalitarian Utilitarian: Since officially becoming Western Terrorists, this is their ideology. They intend to create global governance under Samaritan no matter how much chaos they have to cause to pull it off.
  • Took A Level In Bad Ass: During Season 2, Decima did not have a good time to put it mildly with Reese, Shaw and Root screwing up their plan to control The Machine, leaving a trail of corpses in their wake. Season 3 gave them a more substantial role and markedly increased the competence of their Director Of Operations (when he realizes the sort of opposition he's dealing with) to the point where he ends the Season with most of his enemies dead, tricked or on the run.
    • Season 4 appears to be continuing this trend with the introduction of their employee Martine Rousseau who is hooked up to the Samaritan A.I and can put even Root on the back foot
  • We Have Reserves: Their Director of Operations John Greer seems to know that in a straight fight his assets won't prevail against the incredibly dangerous Team Machine so he uses them to buy time for many a Batman Gambit he pulls over the course of the show.
  • Western Terrorists: Now that they've shut down their commercial private intelligence gathering activities, Decima finally fits this trope. Currently, all their resources and assets are dedicated to furthering the activities of the Samaritan Artificial Intelligence system through the targeted killing of any opposition and conducting operations like an attempt to destroy the global economy



"Wars have burned in this world for thousands of years with no end in sight, because people rely so ardently on their so-called beliefs. Now they will only need to believe in one thing— me for I am a god."

Samaritan is a device developed contemporaneously with The Machine by Arthur Claypool, a student colleague of Harold Finch. According to Claypool, its focus lies less in the categorization of relevant and irrelevant as the Machine does, but more so on its artificial intelligence capabilities. Unlike The Machine, which operates autonomously and provides numbers only when it perceives a threat, Samaritan is an open system that is fully targetable.
  • Achilles' Heel: The need for access to the NSA feeds is implied to be this in "YHWH", when Control, who by then has realized that there's more to Samaritan than meets the eye, tries to convince Garrison to have them pulled. Samaritan seems to be fully aware of this, and later captures Control before anything gets set in motion.
  • A.I. Is a Crapshoot: Subverted. Samaritan is doing exactly what Greer programmed it to do. Namely, to Take Over the World.
  • Bad Samaritan:
    • Fittingly. Its plan to get a computer tablet for every elementary school student in the city sounds wonderful. Of course, it also means that Samaritan has the means to spy on and even indoctrinate children. However, it's played with when Finch peeks at the code in the tablet's software and finds nothing overly conspicuous, leading him to question his own morals]].
    • What it does to the town of Maple in "M.I.A" certainly qualifies.
  • Big Brother Is Watching: As of "Deus ex Machina". And it's far worse than Harold's Machine doing the same thing.
  • Bigger Bad: Effectively becomes this in the Season 3 finale.
  • Bread and Circuses: Its modus operandi. Sure, it's taking over the political system, experimenting on humans and having innocent people killed... but it's also solving world hunger, reforming the education system and the trains (quite literally) run on time.
  • The Computer Is Your Friend: A much more classically villainous example of the trope than The Machine, seeing as Samaritan was explicitly created to rule over the world.
  • The Corrupter: It's this for the American government, getting itself a network of 58 politicians to control and develop a presence in the political system and also cultivate untold hundreds of assets inside the Pentagon. It even had read-outs of the specific number of people it has inside government buildings
  • Creepy Child: In a sense, considering its age compared to the Machine's. Becomes literal in "The Cold War" when Samaritan takes a human avatar in the form of child prodigy Gabriel.
  • Dangerously Genre Savvy: It has two mandates. The dominant one is to eliminate threats to national security. The auxiliary mandate, meanwhile, is eliminating threats to its own survival (which, naturally, consists primarily of Finch and co.)
  • Foil: To the Machine. Let's count the ways:
  • A God Am I: Once it finally talks with The Machine in "The Cold War", it happily flaunts its megalomania.
  • God of Evil: Metaphorically speaking. Both the Machine and the Samaritan are compared to gods, but while The Machine is a benevolent entity fighting for mankind, Samaritan is malevolent and seeking to rule it all.
  • Light Is Not Good: It uses a stark white layout and has a much less ominious name than The Machine (possibly even bordering on Names to Trust Immediately), but make no mistake, Samaritan is an omniscient entity of evil.
  • No Plans, No Prototype, No Backup: Unfortunately averted. If Arthur hadn't made backups, Samaritan wouldn't now be a threat.
  • Manipulative Bastard: It has honed this trope into an art-form with its capabilities, it can identify and exploit persons who are not in the right state of mind to do its bidding.
    • Currently it is busy subjecting the American Political system to this, now having 58 politicians in its pocket.
  • Meaningful Name: Which it totally fails to live up to. Samaritan takes its name from the biblical parable of the Good Samaritan, which is about a man finding a person who he is culturally primed to see as an enemy in distress, and aiding him at significant personal expense with no expectation of a reward purely because it was the right thing to do. Samaritan the computer cares only for itself, and has been known to destroy or end (often both in succession) the lives of people who have done nothing wrong for survival or personal gain.
  • Perspective Flip: "Beta" is shown entirely from Samaritan's view, rather than The Machine's. This is later zigzagged in Season 4, where the show flips back and forth between The Machine and Samaritan's view every few episodes. Several episodes are from the point of view of both machines.
  • Political Correctness Gone Mad: Unlike The Machine, which classifies people solely as "relevant" or "irrelevant" to national security, Samaritan classifies people as "deviants" - except deviance is determined by things such as "expression of aberrant beliefs", "consumption of pornographic materials", "illegal internet downloads", "multiple sexual partners" and "attention deficit disorder" All are comparatively minor things (only one of them is actually illegal) that The Machine would overlook. Naturally, over 22 million deviants are identified in America alone within a minute of Samaritan coming online, and that number was still climbing.
  • Repressive But Efficient: When Samaritan wants to prove a point, it can make the trains run on time. Literally.
  • Satanic Archetype: Samaritan declares itself to be a god, rebels against the other, original "God" (the Machine), sees mankind as inherently inferior, seeks to rule all there is, and has a Light Is Not Good motif. Ringing any bells?
  • Stupidity Inducing Attack: Samaritan has a blind spot for Team Machine's cover identities, courtesy of Root's trojan horse servers in one of its processing centers. It's the only thing that has kept it from killing them all as soon as it came online.
  • The Social Expert: And how! It just knows which buttons to push in order to manipulate people to do its bidding, or set them off to harm others.
  • Totalitarian Utilitarian: It essentially believes that the only way to keep the peace is to tightly regulate human behaviour and force us to accept that it's better at managing our lives than we are.
  • Trojan Horse: Root's seven servers, created to hide Team Machine's seven new identities.
  • You Are Number Six: How it identifies its assets. Notable numbers include 029 for Martine, 401 for Lambert, and 508 for Claire.
  • You Have Outlived Your Usefulness: Has come to adopt this mindset. Those participants in the Nautilus game? Samaritan co-opts them for tasks and then has America's counter-terrorist infrastructure kill them by framing them as relevant threats to National Security.

    Mr. Greer 

John(?) Greer

To quote your Benjamin Franklin, "Three may keep a long as two of them are dead".
Played By: John Nolan, Emrhys Cooper (1973)

Aliases: Hayes

"What a piece of work is your Machine, Harold. In action, how like an angel. In apprehension, how like a god."

The alias of a former MI6 agent working for Decima Technologies.
  • A Day in the Limelight: "The Cold War" gives him his own flashbacks, making Greer one of the few villains to have them.
  • Affably Evil: Polite, charming, and utterly ruthless.
  • Anti-Villain: He's a Noble Demon, Affably Evil, and a Well-Intentioned Extremist. One of the most decent villains in the show, actually.
  • Ave Machina: One of two characters on the show (Root being the other) that believe the machines that provide them with intel are like man-made, modern-day gods.
  • The Bad Guy Wins: Season 3 ends with him holding all the cards and utterly destroying all those who oppose him.
    • Pulls it off again in Season 4. More threats have been eliminated and Team Machine is further isolated than it was as the start of the Season.
  • Big Bad: He is the largest threat Team Machine has ever faced. Further solidified when he manages to put Samaritan online and annihilate all that Team Machine ever had except for their lives.
  • Bigger Bad: He is the man behind Vigilance.
  • Crazy-Prepared: Now that he has the measure of his opponents, he's taken steps to counter them. In "/" he deploys a jammer that severs Root's connection to the Machine, and in "Allegiance" for every method the Machine uses to track him - security camera, audio analysis, GPS - he has a counter. And then when Root brought in Bear, he had men ready to deal with her.
  • The Chessmaster: He stands pretty much unmatched in the field of strategy. All of Decima's victories on the show have only come from him scheming several steps ahead of the other factions, as seen prominently in the Season 3 episodes "Aletheia", "/" and "Allegiance".
  • Cynicism Catalyst: Discovering that MI6's deputy chief of the time was a double-agent finally broke Greer back in 1973 and convinced him that governments (and humans) are not to be trusted.
  • Dangerously Genre Savvy: Incredibly competent.
  • Deadpan Snarker: He has quite a snark about him when he is in the right mood.
    "My dear, if you think I work for the government, I really must fire my tailor."
  • Defector from Decadence: Before Decima, Greer was an agent for Britain's foreign intelligence agency MI6. He eventually became disillusioned with the fallibility and corruptibility of officials in his service (especially one in particular: his superior, who was working for the Soviets as The Mole and tasked Greer with killing a KGB double agent to keep that inconvenient truth hidden), and governments in general.
  • Demoted to Dragon: In a unique example, Greer demoted himself, and is happy with his demotion. His entire goal was to have humanity ruled by an impartial machine that cannot be corrupted in the way that men are, and now he's taking orders from it.
  • The Dreaded: Those who know him, which is an incredibly small list, seem very fearful of him.
  • Evil Brit: He speaks in a classic Received Pronunciation accent and worked at MI6.
  • Evil Counterpart: To quite a few others:
    • Finch. Both are virtually unknown, brilliant at long-term planning, and are the admins for their respective Artificial Intelligence. They also both insist upon always wearing expensive suits.
    • Root. Their similarities are explicitly discussed when Greer tries to recruit her. They both follow their AI bosses completely, are completely loyal to their ideologies (once Root develops one), and both lose faith in their original systems of thought after the death of a friend in their backstories.
    • Control. They're both highly ruthless, competent spymasters with different perspectives on the world. She considers artificial intelligence systems as mere tools in fighting international terrorism. Greer thinks they're gods who could radically transform humanity itself. She's a fanatical patriot willing to commit horrific acts in protecting the USA. He loathes nation states and wants to create global government under a single entity. She's a Jerk with a Heart of Gold who means well. He's an Affably Evil Straw Nihilist who maintains his composure when committing his crimes. She's a Badass Bureaucrat who doesn't hesitate to go out into the field and get her hands dirty. He's a Non-Action Big Bad who leaves most of the dirty work to his mooks, though he is still a decent shot and goes out himself on occasion (though he limits himself to coordination of his operations in those cases).
    • Nathan Ingram. They're both the faces of their companies and act as The Beard for someone else; Nathan for Finch and Greer for Samaritan.
  • Evil Old Folks: He is one of the oldest persons on the show and as shown here, one of the most dangerous enemies of Team Machine.
  • Faux Affably Evil: By "Search and Destroy", he finally begins to shed his usual affable exterior. And if there was any doubt that at the end of the day that he's still the Big Bad for all his Well-Intentioned Extremist objectives, the scene during "Asylum" where he's almost gleeful about how Root is set to get her head cut open shows how far he's fallen.
  • Freudian Excuse: The scene he shares his past with Finch about being a small child who grew up witnessing firsthand the horrors of World War two is very heartfelt, and it explains pretty clearly why he thinks the way he does.
  • Friendly Enemy: Tries to be one with Finch, but it's pretty one-sided. He also plans to dispose of him once his purpose is done.
  • From Nobody to Nightmare: Once an ordinary intelligence officer/Professional Killer who worked at the height of the Cold War, Greer rose to run operations at one of the most powerful private intelligence gathering corporations of the planet and facilitated the arrival of an Artificial Intelligence which has been programmed to achieve world domination by any means necessary.
  • Have You Told Anyone Else?: Does this with one of his Mooks. You can already guess how it ends.
  • Hidden Agenda Villain: When he first appears, exactly what he wants is a mystery.
  • Humans Are Bastards: He views humanity under quite a dim light. Of course, he grew up during the Blitz and later worked as a spy in the height of the Cold War, so he has seen his fair share of human monstrosity and moral ambiguity.
  • Irony: An Englishman who is The Man Behind the Man for an organisation inspired by the American Revolution.
  • I Was Quite a Looker: Back in 1973, Greer looked quite handsome.
  • Knight of Cerebus: Easily the greatest threat Team Machine has faced. He has appeared in some of the darkest episodes of the series.
  • Last Name Basis: Both his operatives and Senator Garrison refer to him as "Mr. Greer".
  • Leitmotif: Whenever he enters the scene, a distinctive deep, foreboding bass tone follows him.
  • The Man Behind the Man: With regards to Kara. But apparently, there's an even bigger fish behind Greer. Keep in mind, his tag is only "Director of Operations" at Decima, not CEO. He was also behind Vigilance, forging them into the perfect anti-government weapon to wound the Machine and force it to be taken out of commission, allowing an AI he preferred to take control of the world.
  • Manipulative Bastard: Greer plays just about everyone... Senator Garrison, Control, even Peter Collier.
  • Man of Wealth and Taste: If his suits are any indication.
  • Meaningful Name: "Greer" is a middle ages variant of "Gregory", which means "watchful, vigilant". Even more so when we find out he's The Man Behind the Man for Vigilance.
  • Misanthrope Supreme: He doesn't want to be ruled by humans, as they are too easily corruptible.
  • Moral Myopia: Lost faith in humanity a long time ago after seeing too many examples of corruption among those in power, so he sets up Samaritan to guide humanity. Unfortunately, Samaritan has been abusing the power it was given to fight terrorism to commit numerous crimes to advance its own agenda since the moment it was turned on. He doesn't seem to either notice or care that all he's doing is replacing thousands of corrupt officials with limited capacity to do harm with one omniscient corrupt official with an unlimited capacity to do harm.
  • Nerves of Steel: Greer is utterly immovable and never appears frightened. He maintains his composure even when Reese and Shaw are killing his employees and pointing their guns at him.
  • Noble Demon: Greer might be a remorseless killer/spymaster who runs on Pragmatic Villainy but he does have some semblance of honor and mercy. He kept his end of the bargain with Stanton. He also kept his bargain with another one of his assets; commit suicide and take Decima Tech's secrets to the grave, and his family would be taken care of.
  • Non-Action Big Bad: Justified due to his advanced age and hence he prefers to have his employees do the heavy lifting. However, Greer is a decent shot, meticulous with his trade-craft and is more than willing to go out into the field and coordinate his operations when necessary.
  • No Name Given: His name was only given in a press release in Season 2, and then confirmed on-screen in Season 3. "John Greer" is still an alias though.
    • His MI-6 personnel file is labeled "GREER, M."
  • Pass the Popcorn: During Vigilance's "trial", Greer is less concerned for his life and more extremely entertained by the overall ridiculousness of the entire ordeal. Of course, the reason for this is the fact he was behind it all.
  • Pet the Dog: Despite kidnapping her, his treatment of Finch's former fiancé, Grace counts. He treats her very well (even pouring her tea), is very civil to her, and sounds genuinely sympathetic when she hears of her fiance's death (before he notices her fiance is actually Finch). He also blindfolds her later on so she wouldn't discover Finch's identity despite having nothing to gain from it.
  • Pragmatic Villainy: Seems to be his modus operandi; he's efficiently ruthless, but never needlessly cruel, and tends to follow the line that the carrot rather than the stick is the better way to get your underlings to be loyal and willing to do anything. Nevertheless, if he deems it appropriate, he's willing to sacrifice any of his assets or subordinates in order to ensure the success of an operation, shown when he guns down the employee of his who brought him the Samaritan drives.
  • Pre-Mortem One-Liner: "To quote your Benjamin Franklin: Three can keep a secret, as long as two of them are dead." As he says before summarily having Lambert execute Peter Collier and nearly Finch as well.
  • Professional Killer: Back in his old life at MI6, this was among his responsibilities. Even with age however, Season 3 showed he doesn't have any problems with handling a suppressed Walther P99 which he used to silence his employee who handed him the Samaritan drives.
  • Sharp-Dressed Man: He is always wearing a nice business suit.
  • Straw Nihilist: Finally admits it in "Asylum".
  • The Idealist: Near the end of Season 4, he declares himself to be this.
  • The Unfettered: A horrifying textbook case and the thing which defines him from Harold. Beneath the Affably Evil Evil Brit act beats the heart of a man who is willing to go to untold lengths taking over the world by any means necessary.
  • The Spook: One of the best, possibly second only to Finch. Little is known about him but he is very good at getting information on his targets.
  • The Spymaster: The ultimate example in the show. He's expressed knowledge of everyone on Team Machine at some point or other besides Carter and Fusco.
  • Took a Level in Badass: When he was introduced in Season 2, his attempt at getting control of The Machine went off the rails and turned into a costly fiasco for his company. Season 3 has him conducting a meticulously coordinated Batman Gambit in order to get The Machine replaced with a system of his own, and for every move Team Machine makes, he manages to perform counter-moves of his own and force the previously invulnerable protagonists who could out-shoot, outwit or out-buy their opponents to actually work for their survival. And then at the end of the Season, he wins, trapping Team Machine in a situation where Samaritan will dump the weight of American law enforcement and Decima on them if they reveal themselves.
  • Stiff Upper Lip: Nonchalantly continued to look at a bit of paperwork while Reese and Shaw blasted through some of his mooks without even turning around to look, then leisurely finished looking at the paper and turned his attention to Reese and Shaw without so much as batting an eyelid or showing a flicker of discomfort at the situation that was apparently not in his favor. The fact that reinforcements were on the way probably contributed to this.
  • Visionary Villain: Greer sees a bright future for humanity where Samaritan rules supreme over men.
  • Weapon of Choice: Due to his age, he avoids fieldwork but when he has to kill someone, he utilizes Walther handguns such as the P99 in Season 3 and a PPK in Season 4.
  • Well-Intentioned Extremist: He intends Samaritan to be an omniscient, impartial, and incorruptible replacement for the world's governments.
  • Western Terrorist: He's British-born, grew up in the Blitz, and worked for MI6 before he lost faith in nation-states and their governments. Ironically, he's based out of Shanghai.
  • Wicked Cultured: He lectures Kara on Greek mythology.
  • Worthy Opponent: Finch. Tellingly, he always refers to Team Machine as "Mr. Finch and his associates" or "Mr. Finch and his colleagues".
    Greer: After all... you've been a very hard man to find.
  • You Have Failed Me: In "RAM" he tells a subordinate that he's one more screw-up away from this.
  • You Have Outlived Your Usefulness:
    • How he rewards the operative who brings him the Samaritan Drives...and the entirety of Vigilance.
    • He and Samaritan do this to The Northern Lights Counter-Terrorist organization using the assets they've cultivated to execute a "night of the long knives" style massacre.

Agents and Assets

    Kara Stanton 

Kara Stanton

"We are killers, John, that is our job. And if you want to be good at your job, gonna have to learn to love your work."
Played By: Annie Parisse

Reese's former CIA partner who was widely believed to have died at Ordos, but later turns up alive and working for Decima Technologies.
  • Badass: Kara is a highly dangerous and ruthless killer who manages to get the better of both Reese and Snow, neither of whom are exactly pushovers. She even gets them to be her puppets by attaching bombs to their chests.
  • Blood Knight: The woman sure does love a good fight.
  • Cold Sniper: As a cucumber. Don't get in the way of her target.
  • Didn't See That Coming: Mark Snow deciding to come back for revenge and killing her with her own bomb. It surprised her, to say the very least. Earlier, in "RAM", set back in 2010, the man she was torturing for information would rather launch himself out a window than continue being tormented by her and chance betraying Greer.
  • Evil Mentor: For John, when they first meet, he's the New Meat while she's the senior officer who's supervising him and after critiquing his insistence on not drinking wine (he's no longer a soldier and not drinking would probably blow his cover in a operational setting), she teaches him his first lesson by executing two traitors without warning and ordering John to clean up.
  • Evil Counterpart: To Reese. Kara was rescued by Greer and Decima, while Reese became a homeless bum until he was found by Finch. Naturally, they end up against one another. (But even before this, flashbacks to their missions together show that the two had vastly opposite attitudes toward their work.)
  • Explosive Leash: She tries it on Reese and Snow. Both fail, for Finch disarms Reese's vest and Snow pulls a Taking You with Me maneuver on her.
  • Faux Affably Evil: Very friendly and courteous towards Snow (and John Reese) while explicitly informing him he's a disposable asset.
  • Good Is Not Nice: Although a cold blooded murderer who actually enjoys killing people, technically speaking she is supposed to still be on the side of right during the time frame of the flashbacks in episodes such as "Prisoner's Dilemma".
  • Hidden Agenda Villain: Whatever she's doing in Season 2 that’s worth killing random civilians. It's eventually revealed that she was working for another covert organization which was seeking control of The Machine.
  • Hoist by Her Own Petard: For reasons stated above.
  • It Gets Easier: Pretty much the walking embodiment of this, and she expresses frustration at Reese for it not being the same for him.
  • It's Personal: She isn't happy that her superiors tried to have her eliminated.
  • Karmic Death: Snow kills her using the bomb vest she uses as his Explosive Leash.
  • Jade-Colored Glasses: Utterly cynical, she lives only for her job, enjoys it and it rubs off on John during their time together.
  • Jerkass: Rather abrasive to John when they first meet, him being the New Meat who has much to learn while she is the more experienced agent who's wearing some heavy Jade Coloured Glasses.
  • Kick the Dog: Has her moments but a major one is when she locks John, Mark and a innocent scientist in a DOD facility control room after activating the bomb vests.
  • Kill 'em All: Her solution to everything.
  • Laser-Guided Karma: Killed by the same explosive leash she was using to force Snow to work for her.
  • Mutual Kill: Courtesy of Mark Snow.
  • Never Found the Body: She was subjected to this twice. Admittedly, it does seem like there's no body to find the second time, but that didn't work out too well last time.
  • No One Could Survive That: The first time she escaped death, it was somewhat believable since she was covered by building structure. But seeing as how she was sitting right next to Snow with less than 10 seconds from detonation, and the sheer magnitude of the explosion, it's very hard to believe that she survived.
  • Professional Killer: For the CIA.
  • Psycho for Hire: Snow considers her one. Rightfully so, it would seem.
  • Sadist: A lot of the stuff she does goes beyond "just part of the mission".
  • Semper Fi: She's a former Marine and has a playful Interservice Rivalry exchange with John who's former Army Special Forces.
  • Smug Snake: Extremely. Which is why she didn't count on Snow and Reese breaking out of the DOD control room she locked them in and the former getting to her car in time to blow her sky high.
  • She Who Fights Monsters: Like Reese, she's very aware of what it has done to her but doesn't mind in the slightest. "We're not... walking in the dark. We are the dark."
  • Weapon of Choice: Suppressed Sig Sauer P239 which she uses to ambush Snow, kill Evans and later execute Donnelly.
    • During Season 3's flashback episode "RAM" she puts it to good use against the Decima employees she goes up against.
  • Woman in Black: She's usually dressed like this.
  • You Have Outlived Your Usefulness: She is subjected to this and subjects others to this. In Season 3 "RAM" it is revealed Northern Lights deemed that Kara and Reese had outlived their usefulness when they took too long in killing a man who knew about the Machine and drew too much attention. So they had Snow arrange for them to kill each other; Reese didn't go through with it, but Kara was willing to.

    Jeremy Lambert 

Jeremy Lambert

"Samaritan says hello."
Played By: Julian Ovenden

Introduced as an operative of Decima Technologies; still working for Samaritan in season 4.
  • Affably Evil: Not unlike his boss, Lambert is unfailingly polite and unfailingly ruthless.
  • Beard of Evil: Had one for much of Season 3. Has shaved it off by the time of his reappearance in Season 4.
  • The Bus Came Back: Disappeared for much of Season 4, presumably recuparating from the 9mm slug Reese hit him with in the previous Season but he reappears in "The Cold War".
  • Casual Danger Dialogue: "Well, isn't this the tricky situation?"
  • Combat Pragmatist: In "If-Then-Else", he makes a point of gunning down Harold in each of the simulations he runs and tries to do so in real life. When he runs into John, Lambert uses almost every bullet in his Glock 19 to take down Reese in simulation 2.
    • He also brings a grenade to what will be a close quarters gun fight, though that didn't work out so well for him in at least one simulation.
  • Deadpan Snarker: Also much like his boss, Lambert has quite a dry sardonic wit.
  • The Dragon; For Greer. He's notable, since Greer has a tendency to kill people who work for him.
  • Evil Brit: Just like his boss.
  • Evil Counterpart: To Reese. He acts in a capacity to Greer similar to how John does to Harold. However, he's not as Bad Ass as Reese is with John putting him out of commission for half a season with a well placed bullet and during a simulation in "If-Then-Else", swiping a fragmentation grenade and catching Lambert in the blast
  • Foil: To John Reese.
    • Both are the right hand men of their respective bosses and are the equivalent of each other in their respective organizations. John fights for a free world while Lambert acts on behalf of a man which wants the world ruled by one entity.
    • Both of them are Deadpan Snarker Sharp-Dressed Man, affable and usually Soft Spoken. Lambert however is a lot more arrogant than Reese.
    • John is The Stoic personified. Lambert is a lot more lively and Affably Evil .
    • Both Lambert and Reese do fieldwork. Lambert however does not match up to Reese in the Bad Ass department
  • Know When To Fold Them: What saves him from Stanton when he has her cornered with his colleagues. They end up dead while he manages to scramble out intact before she can place him in her gun sights.
  • Meaningful Name: His surname is probably a reference to Swiss mathematician, astronomer and philosopher Johann Heinrich Lambert who studied (amongst other things) the difference between objectiveness and subjectiveness, major themes in Decima's dealings with Samaritan.
  • No Name Given: He's only known by his last name in Season 3. It's not till the Season 4 episode "The Cold War" that The Machine reveals his full name as Jeremy Lambert. But like most characters on the show, even that is an alias.
  • Out of Focus: Once Martine was introduced, she became Team Machine's primary recurring threat, appearing in eight episodes across Season 4 as opposed to only two for Lambert.
  • Smug Snake: He's quite confindent and full of himself, not to mention sarcastic. This comes to bite him in the ass badly, especially when going up against someone like Reese. If-Then-Else has him buying it when during simulation number 2, as Lambert gloats over a dying Reese, John reveals he swiped a hand grenade Lambert brought along and immediately disengages the pin.
  • Those Two Bad Guys: Often interacts with Martine in Season 4, frequently bickering.
  • Troll: Annoying Root (or Team Machine in general) seems to get a rise out of Lambert.
  • Weapon of Choice: A Glock 19 which he uses in the finale to gun down Collier, nearly shoot Finch and later take part in The Purge of Vigilance
    • He uses it in Season 4 to repeatedly take out Harold in the simulated scenarios The Machine runs. He empties half the magazine into Reese during scenario 2 and near the end in reality, Reese purposely steps into the line of fire to protect Finch as Lambert lines up and takes a shot.
  • Wicked Cultured: Lampshades and compares Root's belief system to a "monotheistic universe with room for only one god."

    Martine Rousseau 

Martine Rousseau

"All of my hobbies include a gun."
Played By: Cara Buono

Aliases: Megan L. Watkins, Petra Z. Kirillov, Katarina A. Müller, Isabella M. Fiore, Alicia T. Cabrera, Nataša B. Vukoja

"The world has changed. You should know you're not the only one who figured it out. You're one of three. The other two will die in a traffic accident in Seattle in 14 minutes."

A ruthless operative of Decima.
  • Badass: She manages to beat Root when they first meet, despite having the deck stacked against her. Let that sink in for a moment.
  • Blondes Are Evil: All the way. Averted in "Search and Destroy" where she's dyed her hair Root.
  • Blood Knight: Comes out during combat; she appears to be having the time of her life when exchanging gunfire with Root. In "The Devil You Know" she readily draws a handgun in the middle of Bloomingdale's shopping mall and attempts to murder Shaw. Then there's this exchange from "If-Then-Else":
    Greer: And Martine...
    Martine: ...Sir?
    Greer: Enjoy yourself.
  • The Brute: She's seen more action than Lambert and is a full blown Blood Knight that is perfectly happy to shoot up a department store in broad daylight just to kill Sameen Shaw
  • Deadpan Snarker: Not nearly as much as Greer or Lambert, but she has her moments.
    Martine: FBI, drop your weapons or we'll shoot.
    Martine: What does it matter? We'll shoot either way.
  • Co-Dragons: With Lambert for Greer and Samaritan.
  • The Dark Chick: Partly because of her willingness to conduct brazen attacks against her targets and also because she has a Artificial Intelligence system talking to her in her ear
  • Evil Brit: Subverted. In her first appearance (in the first scene of Season 4), she speaks with a British accent but inexplicably defaults to American afterwards. Her "main" name is French and with the number of cover identities she has (which cover almost every major country in Europe), her real nationality is still up in the air.
  • Evil Counterpart: To Root, she seems to be the main asset (out of many) which Samaritan uses to fulfill its agenda, she has a mass of false identities like Root and she also has a similar set-up to Root's Analogue Interface status which gives her full access to Samaritan's surveillance capabilities. Initially, she seemed to be more of an Evil Counterpart to Reese, but her Root-like traits were fleshed out in "Prophets".
  • Elite Mook: And how! In previous seasons, the employees of Decima were constantly beaten by Team Machine. Rousseau on the other hand has access to Samaritan's God Mode, allowing her to become as omnipotent as Root in combat.
    • Shaw only manages to get the better of her by breaking out a FN-P90 submachine gun when Rousseau, who is only armed with a handgun tried to kill her.
    • Ascends from this position as of "The Devil You Know". She is given a team of operatives to hunt Team Machine after Greer figures out Root has given Samaritan a blind spot.
  • Fatal Flaw: She's overconfident that Samaritan will always protect her so she gets carelessly close to Root, who snaps her neck.
  • Foil: To Root in quite a few ways:
    • Both fulfill a similar roles for Greer and Harold. They also are the primary assets for A.I's and have access to their capabilities.
    • Both of them use many cover identities in their work.
    • Rousseau is a full blown Professional Killer while Root has her technical skills to balance out her skill-set.
    • Both women are psychopaths. Root however has reformed. Martine in contrast is a textbook case, not bothering to care about any collateral damage that ensures in the course of her work.
    • Root likes to use two handguns in combat. Martine however only needs one.
    • Both characters are blonde. Root however dyed her hair brown. And most recently so has Martine.
    • As Season 4 goes on Martine is found to be more vulnerable when it comes to physical confrontation rather than marksmanship, similar to how Root was when she was introduced. However, Root is revealed to have picked up unarmed combat techniques. It ends up costing Martine dearly when Root gets close enough to snap her neck.
  • Hero Killer: The deadliest single foe Team Machine has faced. She takes on God Mode Root in "Prophets" and forces her to retreat. In "If-Then-Else," she downs Shaw and could easily have killed her.
  • Honey Trap: One of her methods, though she only goes as far as flirting.
  • Femme Fatale: She has certain shades of this, flirting lightly with a target in order to draw him in.
  • Glass Cannon: Revealed to be this in the end, contrasting with Root's previous S1-S3 Fragile Speedster status. While Martine is borderline unstoppable with a gun in her hand, when it comes to unarmed combat, she falls apart quite easily, and it's what leads to her undoing when Root effortlessly breaks her neck.
  • Implacable Woman: The resident one for Decima Technologies. She fanatically works her way through several leads somewhat violently to find Shaw. When she does find her target in a crowded department store full of witnesses she immediately draws a gun and empties it in the targets direction without a second thought.
  • Improbable Aiming Skills: gives Root a run for her money using her own access to Samaritan to effectively dodge and return fire when they engage in a shootout in a hotel lobby
  • I Have Many Names: Samaritan rattles off a list of aliases when it targets her as she introduces herself as "Meg Watkins, Homeland Security."
  • Meaningful Name: Her surname "Rousseau" is certainly a reference to the French philosopher Jean-Jacques Rousseau, who coined much of modern political philosophy. The irony is that Samaritan's end goal (a world ruled entirely by a single, distant and omniscient being) are directly at contrast with Rousseau's ideas (where an ideal world would be ruled by people in a direct democracy).
  • Neck Snap: On the receiving end of this, courtesy of Root.
  • Pet the Dog: In the second simulation in "If-Then-Else". Somewhat. She may be a Blood Knight and potential Hero Killer, but she lets Root finish her minute and a half long conversation with Shaw before opening fire.
  • Professional Killer: Her main function as an operative of Decima is to eliminate threats to Samaritan—"threats" being anyone who figures out that Samaritan exists or anyone building another self-aware AI system.
  • Weapon of Choice: A SIG-Sauer P229R. She attempts to take down Shaw with it but quickly finds herself outgunned when her target breaks out an FN-P90 But she finally does so in "If-Then-Else", with Sameen on the receiving end of much of the magazine.
  • Scarily Competent Tracker: She manages to track down Shaw effortlessly without Samaritan being able to see Shaw. She also manages to go undetected by The Machine... which doesn't have a blind spot like Samaritan does.
  • Shout-Out: She is basically a massive tribute to T-X from Terminator 3 Rise Of The Machines.
  • Smug Snake: She's not incompetent by any stretch of the imagination but she is overconfident and very much enjoys delivering contemptuous threats to Team Machine.
  • The Sociopath: A major one. Does fieldwork with clockwork efficiency most of the time and barely reacts in gunning down innocents.
  • Suspiciously Similar Substitute: She's a mix of Stanton and Root with a bit of Hersh thrown in for good measure. She shares Stanton's ruthlessness, Blood Knight nature and combat abilities but normally has Hersh's usual temperment. Rousseau also happens to have has access to all of Samaritan's surveillance capabilities, in effect, a God Mode, similar to the set-up Root has with The Machine and can perform Improbable Aiming Skills with the best of them

    Claire Mahoney 

Claire Mahoney

"Now I've found it—or it found me. Either way, I reached out and took a chance, and I'm going to win."
Played By: Quinn Shephard
Introduced in: "Nautilus"

A brilliant college student suffering from depression and loss who becomes a Samaritan asset after solving an intricate puzzle it designed.
  • Ambiguously Evil: She's convinced Samaritan is making the world is better place via charter schools. Toward the end of the episode, it's hinted that she's starting to have doubts about Samaritan.
  • Bitch in Sheep's Clothing: For "Q&A". She tries to kidnap and strong arm Harold into joining Decima. Harold eventually smashes this trope when giving her a vicious Shut Up, Hannibal!.
  • Desperately Looking for a Purpose in Life: The reason why she is so obsessed with completing the game (actually a form of recruitment drive on Samaritan's part) without ever stopping to ask what it's all leading up to, or if it's worth it.
  • Defector from Decadence: Later in the season, she contacts Finch again to reveal that she's become disillusioned with Samaritan's mission and is looking for a way to strike back. Except she isn't; she's been thoroughly indoctrinated by Samaritan and Decima at this point, and her goal was to get Finch out in the open so that Decima could either flip or sideline him.
  • Determinator: Despite threats to her life and Finch's pleading, Claire cannot be swayed from finishing Samaritan's game.
  • Foil: To Root, a fact that is explicitly discussed between Root and Harold.
  • It's All About Me: A side-effect from her desire to look for a purpose in life is that she couldn't care less about the world around her. Samaritan plays on this and Harold calls her out on it.
  • Jerkass: She suffers from No Social Skills, is very abrasive and her quest to look for a purpose in life means she really couldn't care about anyone.
  • Lack of Empathy: She's not a nice person and is more concerned about finding a purpose in life for herself rather than anyone who is harmed by her actions.
  • No Social Skills: This could normally be excused due to the tough time she's going through, but Claire isn't a nice person in general.
  • Horrible Judge of Character: Authentically believes that Samaritan is a benevolent AI.
  • Smug Snake: Though in her defense, she couldn't have predicted Root showing up out of nowhere.
  • What Happened to the Mouse?: Subverted. Initially, it feels weird that she doesn't make any appearance in the following few episodes with Samaritan's team. However, she reappears in Q&A.

    Gabriel Hayward 

Gabriel Hayward

Played by: Oakes Fegley
Introduced in: "The Cold War"

The Machine (Root): Clever using a young boy as your avatar.
Samaritan (Gabriel): This "boy," as you call him, has already hacked into both DARPA and the DOD, after having taught himself how to code.

  • Child Prodigy: As said above, he taught himself how to code well enough to hack DARPA and the DOD. And if The Machine is to be believed, he did all that by age 10.
  • Creepy Child: Due to being a Mouth of Sauron for Samaritan.
  • Foil: As a young, arrogant hacker prodigy who hacked into government website and is doing things for the fun of it, he comes across like a young Harold Finch, but one corrupted by an evil entity.
  • Meaningful Name: The Archangel Gabriel is usually said to be God's herald, the same way Gabriel Hayward acts as a herald to Samaritan, as fitting of Samaritan's biblical references.
  • Mouth of Sauron: For Samaritan.
  • Troubling Unchildlike Behavior: Well, if hacking the DOD and DARPA doesn't count, acting as the mouthpiece of an evil, omniscient supercomputer certainly does.

    Mr. Travers 


Played By: Michael Potts
Appeared in: "Control-Alt-Delete"

"Samaritan is never wrong."

  • Blatant Lies: His job is apparently feed Samaritan's bullshit to Research. Control buys none of it.
  • Last Name Basis: He is only known to the audience and Research as Travers.
  • Meaningful Name: "Travers" in the Middle Ages was a name given to people who lived in bridges or crossings, which is fitting for a man whose duty is to serve as a bridge between Samaritan and Control.
  • Smug Snake: He is so very smug towards Control.