WARNING: UNMARKED SPOILERS BELOW. CONTINUE?
ENCRYPTION CODE: [CLASSIFIED]
CLASSIFICATION: INTERNAL AFFAIRS
SUBJECT: OFFICE OF NAVAL INTELLIGENCE
- Main Index
- UNSC (Miscellaneous Personnel)
- The Covenant
- UEG Civilians
- Other Factions
Office of Naval Intelligence (ONI)
Officially the intelligence gathering and counter-espionage division of the UNSC, ONI's actual operations cover a much broader range of activities, and it has an alarming tendency to act without the knowledge or consent of both the UEG and UNSC High Command. Extremely controversial, both in-universe and within the fandom.
- Big Bad: The organization as a whole is this for HUNT the TRUTH, due to the focus being on creating a Broken Masquerade.
- Big Brother Is Watching You: Oh, so very much. Throughout HUNT the TRUTH, they cut off Waypoint access for the outer colonies, plant false evidence, terminate bank accounts and even capture Ben. And they really are watching you - even if you're on a glassed planet or in an underground bunker, you're not safe.
- Cassandra Gambit: When Benjamin Giraud comes close to breaking the truth on the SPARTAN-II program, ONI's able to counter it by deliberately leaking truthful information to Ben, but incorporating an easily detectable flaw in the actual files so that, in combination with Manipulatively Editing their previous footage of him and forcing his sources to recant, he'll be discredited in the public eye.
- Even Evil Has Standards: A purely case by case basis (Halsey, Watanabe, Haverson, Dare, maybe Parangosky and Ackerson when they're not acting hypocritical about it). On the whole, however, there doesn't seem to be anything ONI won't consider doing.
- Fascist, but Inefficient: The Office of Naval Intelligence acts like it has an Omniscient Morality License, holds people in perpetuity and summarily executes those who have broken their rules without trial, and has a moral compass so off kilter that you can't even tell it's there. Yet they cause more screw-ups that the protagonists have to end up fixing. The four sections that make ONI are extremely suspicious of each other, and it's implied that it was intentionally set up this way by Admiral Parangosky.
- Fun with Acronyms: Oni, as in the Japanese demon. You really have to wonder how naming themselves after a kind of monster has affected their reputation in Japan or Japanese-speaking colonies.
- Government Agency of Fiction: Naturally.
- Government Conspiracy: Several going on at once, to the point that they're effectively a shadow government within the UEG. Their biggest is to become the true power behind HIGHCOM.
- He Who Fights Monsters: ONI's goal is the preservation of humanity, but they do some very questionable things to achieve it. Like the SPARTAN Program, or instigating a Civil War in the Elites post-HeelFace Turn to keep them from attacking Earth again. The former works great, the latter not so much.
- In-Series Nickname: Unsurprisingly, its agents are referred to as "spooks".
- Internal Affairs: Section Zero is officially charged with rooting out illegal programs, though in practice they seem to be more there to ensure that nobody in ONI goes against the CINCONI's will.
- Kidnapped Scientist: ONI is not above forcibly "recruiting" academics for its projects.
- Lensman Arms Race: Section III and the groups it oversees are the ones taking point on the UNSC side, being responsible for developing most of the UNSC's most advanced technology, such as MJOLNIR and the Spartan Laser, and reverse-engineering Covenant and Forerunner technology.
- Mad Scientist: Some of ONI's more ridiculous science projects, like trying to control the Flood while giving them live prisoners to infect, creating genetically modified crops to starve the Elites, and creating a barely controllable Synthetic Plague designed to liquefy its victims, gives one the impression that they employ quite a few of these.
- Manipulative Editing: Stock-in-trade for Section II's propaganda machine.
- Masquerade: In charge of several, with one of their biggest appearing in HUNT the TRUTH; if you know Halo lore, you'll recognize that the stories Giraud's ONI-supplied sources give about the origins of John-117 and the other Spartan-IIs are all fabrications (among other things, they claim that John didn't leave his hometown until he was at least thirteen year old; As You Know, John was actually kidnapped and taken offworld at six years old. They're not referring to the flash clone either, which died only a few months after the original abduction).
- Broken Masquerade: In Episodes 8 and 9 of HUNT the TRUTH, Benjamin Giraud leaks all information he has (a sizable amount, including all of what there was on the flash cloning and various other dirt) regarding the SPARTAN-II program to the general populace, first over the internet, then over a live television broadcast. The colonies, especially the Outer Colonies, are furious. However, ONI is able to enact a Cassandra Gambit that successfully discredits Ben enough to put out much of the fire.
- The Men in Black: Their agents are sometimes depicted as this, particularly in media taking place from a UNSC outsider's perspective.
- Morally Ambiguous Doctorate: Section III is effectively the UNSC's premier R&D division, and many of its projects are quite shady (the SPARTAN-II and III projects being case in point).
- Nice Job Breaking It, Hero!:
- ONI accidentally told Jul 'Mdama of their plan to keep the Elites in a prolonged civil war in order to prevent them from attacking humanity, and also gave him access to both information about the Didact and a means of escaping his captivity. The rest is history.
- The plan to foment civil war among the Elites also counts in and of itself, largely because ONI is doing so by helping to foment an uprising against the Arbiter, who's already busy trying to convince his people that peace with humans is a good thing. It's the equivalent of Country A helping kill the primary candidate for Country B's leadership, whose foremost policies call for peace with Country A, when the runner-up is a blatant anti-Country A supporter. In practice, ONI's festering of Elite militancy has mostly just resulted in the creation of numerous renegade factions with enough strength to attack and even completely overrun human worlds, as seen in Spartan Assault, Halo: Escalation, and Halo 4, with the irony being that the Arbiter's still substantial sway over the former Covenant races is apparently the only reason why things aren't even worse for humanity.
- In fact, it takes a lot of lucky breaks to prevent ONI's "start a civil war" plan from falling apart and getting exposed before it's even set in motion.
- They also kept information hidden from Dr. Halsey, and then ordered her execution when things went south. Then Dr. Halsey defected to the Covenant.
- Yes, every problem the Arbiter has after the war and the Chief has to deal with in Halo 4 you can blame on ONI.
- ONI accidentally told Jul 'Mdama of their plan to keep the Elites in a prolonged civil war in order to prevent them from attacking humanity, and also gave him access to both information about the Didact and a means of escaping his captivity. The rest is history.
- No Such Agency: ONI has a number of "theoretical" sections whose purpose and influence are unclear to all but the very top of ONI.
- Professional Killer: Naturally, ONI agents are generally quite well-versed in assassination.
- The Professor: Many, if not most, of the UNSC's brightest academics, scientists, and engineers work for ONI (willingly or not), largely in Section III or other, even more secret, divisions.
- Propaganda Machine: The whole purpose of ONI Section II.
- Improperly Paranoid: By 2552, they're just overly paranoid of everyone, including their own personnel.
- Right Hand vs. Left Hand: Oh, god, they play this hard.Black Box: Is ONI one happy family? Oh, please. We've got four divisions, officially, and only one of them knows that we've actually got more than that. There's Section Twomade up of psyops and PR, who each kid themselves they're not like the other at allwhich tells the lies; Section Zero, which thinks it spies on everyone else, tells lies to Section Two, and thinks it tells lies to Sections One and Three; Section One does stuff we can almost talk about, the interface with other branches; and Section Three does the stuff we can't talk about or else it would have to kill everyone in fascinating and groundbreaking new ways.
- Sinister Surveillance: Where to begin? They have access to pretty much every recording/live-feed device in the entire UNSC, and casually hacking into private correspondences/records is basically a typical day for them.
- The Spook: Employ several, naturally.
- The Spymaster: Specifically, Section I is the branch officially in charge of "proper" intelligence-gathering, though the other sections do plenty of spying of their own.
- State Sec: While ONI started off as merely one of many intelligence agencies, Parangosky's leadership and the war with the Covenant have turned it into not only the sole remaining intelligence agency, but perhaps the most powerful branch of the UNSC.
- Stealth in Space: The vast majority of the UNSC's stealth-capable ships are crewed by members of ONI's Prowler Corps, with the most advanced Prowlers incorporating both Covenant active camouflage and Forerunner baffler systems.
- Unwanted Assistance: The problems with ONI's plan to prevent the Sangheili from posing a threat to the UNSC by starting a Civil War among them while the rest of the UNSC is trying to make a peace treaty with them are finally pointed out In-Universe in Halo: Mortal Dictata, when even some of Kilo-Five's own people express their concerns about the potential blowblack.
- Ungrateful Bastard: Their short-sighted plan to stir up trouble amongst Thel Vadam's people reeks of this trope.
- Well-Intentioned Extremist: When looking at them on a good day. The SPARTAN-II Program has been receiving a lot of backdraft in universe for its questionable actions, yet when the Insurrection was ongoing no one seemed to mind kidnapping and conscripting 75 children against their will. And it's implied the backdraft is not because of a sudden case of morality (as you have read and will read, ONI has no sense of morality), but just to make the SPARTAN-IV Program seem better.
Admiral Margaret Orlenda Parangosky (00230-00923-MP)
The aged head of ONI for the entirety of the Human-Covenant War, Parangosky was the most powerful and influential human in the UNSC, even more so than the rest of HIGHCOM and the President of the UEG. She has her hands in every piece of dirty business in the UNSC, and is dreaded by nearly everyone who knows she exists except for Lord Hood (and that's only because he's the only person alive who outranks her) and Doctor Halsey. Sometime after the war, she steps down from her position, giving it to her protégé Serin Osman.
- Almighty Janitor: Even when she was just a captain, she was able to take down rivals who were much higher-ranked, in large part thanks to her taking control of the Department of Colonial Security when no one else wanted it, giving her an army of civilian spies loyal to her alone.
- Anti-Hero: See Nominal Hero below.
- Bad Boss: If you annoy her to the point of being a potential liability, she will likely have you killed, at the very least.
- Benevolent Boss: One of her few redeeming qualities is that if you do your job, don't lie to her or plot against her, and avoid screw-ups, you'll be looked after extremely well.
- Comfort Food/Trademark Favorite Food: Ginger nut cookies.
- Conspiracy Theorist: Her motto is "Strength through Paranoia".
- Dirty Business: Fully acknowledges that normal ethics and morality get tossed out the window at ONI, and regards the SPARTAN-III program as a "regrettable" necessity. She even notes in the opening to Halo: The Thursday War that there's a lot of things she wishes she could "unsee and unhear".
- The Dreaded: Everyone is afraid of her, and with good reason. As the most powerful human alive and head of ONI, she can pretty much erase you from existence if you get in her way. Hood and Halsey are the only ones to have stood up to her, and the latter pays dearly for it.
- Even Evil Has Loved Ones: Genuinely cares about Serin. Bear in mind, she's one of the few people Parangosky does care about.
- We later learn that she was also good friends with BB's original brain donor, Dr. Graham Alban.
- Evil Old Folks: Extra emphasis on the old. She's over 90 years old by the 2552, and still running ONI.
- Heel Realization: By the time she sends Halsey to help the Infinity, she sends a letter to her apologizing for the less than ideal conditions she had held the latter under when imprisoned, and acknowledges that she doesn't really have a position to ask for personal favors, but appeals to Halsey's desire to help humanity instead. Her protege takes up the evil part instead.
- Hypocrite: In Glasslands, immediately after talking about how the SPARTAN-IV project is going back to "using consenting adults now, like we did in Project Orion" and berating Halsey for the child soldier part of the S-IIs, Parangosky then declares that the surviving Spartan-IIIs (who, with a few exceptions, are twelve to thirteen years old at most) will still remain in service (though to be fair, Word of God implies that the survivors of Gamma Company were given a choice about whether to stay after the war).
- She also conveniently never brings up her commissioning of the SPARTAN-III program which was equally immoral, in different ways, and didn't involve Halsey at all.
- Her plans to expose the various immoralities and war crimes of ONI, the UNSC, and the military comes across as her sanctimoniously throwing a bunch of middle-men and subordinates to the wolves while she, one of the key architects, gets away mostly unpunished. She's continuing to use both the Mark II's and III's past the point where it could be strictly considered 'necessary,' and seems to be holding off until she personally has nearly nothing left to lose.
- Ice Queen: Gives Truth a run for his money in sheer coldness.
- Insane Admiral: Overly paranoid, spiteful and tried to actively destabilize humanity's only real ally among the Sangheili. The only reason she was still in charge until her voluntary retirement is because she knows where the bodies are buried. Because she's the one who made them bodies in the first place.
- Iron Lady: Widely considered the scariest individual in the UNSC for a good reason.
- It's Personal: Much of her antipathy to Halsey seems to come from the fact that one of her closest friends, Dr. Alban, committed suicide over his guilt about his role in the SPARTAN-II program.
- Karma Houdini: Authorized the creation of three companies of Laser Guided Tyke Bombs whose sole purpose was suicide missions, organized a Civil War among the Sangheili when the UNSC were trying to make peace with them, and promotional messages for Glasslands imply that she intentionally left Reach vulnerable to give Operation: RED FLAG a chance for success. And this is just the stuff we know about. Yet she seems to have gotten away with it without any sort of repercussions.
- Ironically, she plans to subvert this. She thinks that she should not get away with what she has done, and is putting together evidence and files to present to the UNSC judiciaries so that she and everyone else involved in the Spartan-II and III projects will be prosecuted. Given her age though, any punishment is not likely to last long before she dies.
- Kick the Dog: Planned on telling Halsey that her hated rival Ackerson had died a hero, but only after informing her of the death of Halsey's daughter Miranda.
- The Man Behind the Man: She's the one who is actually instigating and arming the Sangheili dissidents in the Kilo-Five Trilogy, thereby providing half the conflict for the series. She would be the Big Bad if not for the fact that the Kilo-Five team, which are taking her orders, are the Heroes of the trilogy.
- Never Mess with Granny: Even though she can't actually beat anyone up personally, even badasses like ODSTs and Smug Snakes like Ackerson take one look at her and know she is not someone to annoy. Cross her, and she will bury you, likely literally.
- Nominal Hero: Whether it's a case of He Who Fights Monsters or simply being a straight-up villain is the only part open for interpretation.
- The Spymaster: The head of ONI.
- Took a Level in Kindness: Finds herself acting friendlier to her subordinates the more she ages, though this really isn't saying much, considering how unrepentantly ruthless she remains even at her old age.
- Unscrupulous Hero: And that's assuming you even consider her one of the heroes.
- The Unfettered: There is nothing she would not do to secure humanity's safety and future.
- We Have Reserves: Authorized the creation of three companies of Laser Guided Tyke Bombs to serve as Cannon Fodder.
Admiral Serin Osman (formerly Serin-019 and born Serin Çelik) (39489-72738-SO)
A former member of the Spartan-II program, Serin "washed out" when her body rejected several of the first round of genetic enhancements. She was recruited by ONI, who repaired the damage done to her, and she became the protégé of ONI head Admiral Margaret Parangosky, from whom she takes the reins after Parangosky's retirement.
- Action Girl: She was one of ONI's top agents for a long time and more than capable of taking care of herself even without the normal Spartan upgrades.
- Anti-Hero: Before she became head of ONI, anyways.
- Benevolent Boss: She might be career ONI, but she will stick her neck out for Kilo-Five's sake. Even after becoming CINCONI, she can be surprisingly kind to valued subordinates.
- Bad Boss: That said, she's also inherited some of Parangosky's more ruthless people management strategies.
- Best Served Cold: She waited a long time to get revenge on Dr.Halsey, but is not as satisfied as she hoped she would be after arresting her, instead just feeling relief and contentment that it was over. That said, she doesn't seem to mind ordering Halsey killed after she gets captured by Jul 'Mdama.
- The Captain: To Kilo-Five, back when her rank was literally still captain.
- Daughter of a Whore: The daughter of junkie prostitute Pinar Çelik.
- Defrosting Ice Queen: Towards Kilo-Five, and Kilo-Five alone.
- Dirty Business: At least at the time of the Kilo-Five books, she expresses distaste for her ONI work, even questioning her own motivations about using Naomi as a negotiating point with Staffan.
- Disappeared Dad: Not even ONI could figure out who her father was.
- Empowered Badass Normal: Subverted, due to her physical augmentations failing. However, several of the mental ones took, making her extremely smart.
- Good Is Not Nice: During her more idealistic years.
- Heroic Bastard: Though after she takes control of ONI, you can potentially hold the "heroic".
- I Owe You My Life: Seems to have this sentiment towards people who look out for her; she definitely has it with regards to Parangosky, and she even decides to go all the way back to her old homeworld to thank her old teacher, whom she doesn't even remember, for being the only person to care about her during her childhood.
- Iron Lady: She definitely takes after her mentor in this department.
- Jumping Off the Slippery Slope: Despite her hopes that she would be less ruthless as the head of ONI than Parangosky, even vowing to reveal the truth about the Spartan-II project, so far it appears that ONI under Osman's regime has been just as, if not even more, brutal and suppressing. The end of HUNT the TRUTH's first season reveals that not only did ONI instigate a massive cover-up of the SPARTAN-II project's dark secrets after rumors of them were threatening to get out of hand by allowing the truth to be briefly "leaked" before utterly discrediting the source, they even briefly let John-117 be considered a traitor by the public and threw poor Benjamin Giraud into Midnight Facility to be locked up forever. So much for any hope of Osman being a more ethical leader than her predecessor.
- Morality Pet: To Admiral Parangosky. She has her own in Kilo-Five.
- Obsessed with Food: Seems to have been this as a child; ONI caught her by offering her a burger, and she had a habit as a trainee of eating everyone else's leftovers. It's understandable given her impoverished background.
- Parental Neglect: Her mother was not a Hooker with a Heart of Gold, to say the least; ONI didn't even bother to replace her with a clone.
- Pragmatic Hero: Is willing to carry out ONI's very morally ambiguous work even when it makes her uncomfortable. After taking over command of ONI, she is still willing to order such operations herself, including the assassination of Halsey after she is captured, to the point where it's hard to consider her a hero at all anymore.
- Rank Up: As part of her plan to have Osman succeed her, Parangosky is having Osman promoted as soon as she reaches the minimum age requirement for the post. The beginning of Halo: Mortal Dictata has her get promoted to Rear Admiral, lower half, on her birthday. By Halo 4, Osman's become a full Admiral and head of ONI.
- The Spymaster: Naturally, given that she currently leads ONI.
- Street Urchin: Outside of her teacher, her main source of food was digging through garbage cans.
- True Companions: Comes to regard Kilo-Five as her friends.
Colonel James Ackerson
A UNSC Army officer and ONI Liaison Officer, as well as the secret head of the SPARTAN-III project. A rival of Dr.Halsey, he did his best to discredit and sabotage her, but failed to get his projects precedence over hers.
- Anti-Hero: To the point of bordering on being a full Nominal Hero, if not for his Pet the Dog moments.
- Ambition Is Evil: No matter how smart or dedicated to stopping the Covenant he is, he mixes it with his own personal ambitions, case in point being his efforts to get funding priority over Halsey, up to the point of attempting to get John-117 and Cortana killed during the MJOLNIR Mark V test run (attacking them with ODST squads, anti-tank mines, automated chain guns, and a jump-jet strike fighter armed with autocannons and anti-tank missiles).
- Asshole Victim: Although he's executed after throwing a wrench into the Covenant's plans and making sure his brother and the people of Cleveland have a chance to escape, it's still hard to feel sorry for him.
- Big Brother Instinct: Implied to genuinely care about his brother Ruwan, maybe.
- The Chessmaster: An undoubtedly talented one when he wants to be, but alas, his own arrogance and shortsightedness seem to prevent him from exercising his full potential. Regardless, he is able to escape duty on the front lines of the war after Cortana tried to have him transferred there as revenge for pretty much trying to kill her and John, and he plays Lepidus like a harp while in his captivity.
- Colonel Badass: Was a decorated combat officer before joining ONI. Halo: Uprising shows that he hasn't lost the courage and fortitude from those days; he gets captured by the Covenant in battle, is brutally tortured by Brutes, then manipulates them into sparing his hometown and wasting time and resources during the Battle of Earth, then, (right before his execution) he insults the Brute who's about to kill him and the entire Covenant religion right to his face.
- Colonel Kilgore: Was actually glad Reach was glassed in the hopes that Dr. Halsey and the Spartan-IIs were killed. And that's not even getting started on the Spartan-IIIs.
- Even Evil Has Loved Ones: Played with. Kurt Ambrose says he gets the feeling that "Ackerson would gladly assign members of his own family to a suicide mission if he could find an appropriately high value target to send them against." However, this assumption may have been proven wrong when Ackerson uses his own capture to trick the Covenant into sparing Cleveland in a possible effort to save his brother. Even then, there are some hints that James might have expected Ruwan to be willing to sacrifice himself to deal a blow to the Covenant.
- Also, he's married, though we know little about the nature of the relationship (and whether it survived Cortana hacking into Ackerson's account, sending a bunch of his money to a random brothel, and then sending his wife the bill).
- Evil Counterpart: To Dr. Halsey, although theyre probably not as different at the end of the day as theyd both like to think.
- Face Death with Dignity: Say what you want about the man, but he's certainly no craven, using his last moments to give a "The Reason You Suck" Speech to the Brute about to execute him.
- Glad I Thought of It: Despite hating Halsey for and taking every opportunity to criticize the SPARTAN-II program (largely because his proposals are snubbed in their favor), the one major project he manages to pitch is SPARTAN-III, the foundation of which is naturally based entirely on Halsey's work.
- Hate Sink: We're obviously not supposed to be too fond of him.
- Hidden Depths: He may be a selfish bastard who relishes in shady and slimy bullshit, but Halo: Ghosts of Onyx shows that, at least for a time, he did miss being a regular Army trooper instead of an ONI spook. Halo: Uprising shows that he's not a completely selfish bastard.
- Hypocrite: Apparently, kidnapping and drafting children is unforgivable while sending them on suicide missions is perfectly fine.
- Off with His Head!: How Lepidus kills him during the Battle of Earth.
- Jerkass: Even his own brother can't really deny this.
- Jerkass Has a Point: Designed the Spartan-III program to train crops of young children to be elite suicide troopers so the UNSC could "trade lives for time." Said program ends up stalling the Covenant onslaught long enough for humanity to survive the war.
- Hes an unsympathetic prick about it, but hes also not wrong when he says there is little point wasting lives or valuable warships (especially after they just lost one of their biggest industrial bases) to go back to Reach and confirm what they already know. Any rescues they could attempt for the survivors on the surface are tactically unfeasible.
- Karma Houdini: Played with. After his attempted sabotage of Chief's Mark V test in Halo: The Fall of Reach, Cortana takes revenge by reassigning him to the front lines (and attempting to trick his wife into thinking he's been cheating on her). Halo: First Strike then reveals that Ackerson managed to slip out of said reassignment. However, the Covenant invasion of the Sol system forces him to rejoin the front lines anyways, which ends up with him being captured and executed.
- Lack of Empathy: Ultimately subverted. He seems like this at first glance, but he does have brief moments that can be interpreted as him actually caring for others. They are just about the only humanizing parts of his character.
- Not So Different: Ackerson and Halsey are both arrogant well-intentioned extremists who tend to grate on the nerves of anybody they interact with. The difference being that Halsey is still much more in touch with her humanity, including her various regrets about the SPARTAN-II program, whereas Ackerson's jerkassery more often than not often overshadows any positive qualities he has.
- Pet the Dog: When captured by the Covenant and imprisoned, he lies to them about a fake artifact in Cleveland they need to find, keeping them from destroying the city and thus giving his brother Ruwan a chance to escape.
- It's implied that Kurt and he have a largely positive working relationship.
- Reasonable Authority Figure: Downplayed because of his jerkassery, but Ackerson is very open to Kurt's suggestions about the SPARTAN-III project, knowing full well that Kurt probably knows what he's doing, and does his own best to make sure the program does not want for anything. After all, it's in humanity's (and his own) best interests that everything goes smoothly.
- It's also notable that much of his previously-established animosity is due to bitterness that his proposals and projects tend to be snubbed in favor of Halsey's; SPARTAN-III is one effort he succeeded in pushing, which perhaps serves to pacify him when it comes to running it.
- Redemption Equals Death: Goes down doing his part to help humanity survive.
- Smug Snake: Tends to talk down to most everyone. This includes his own superior officers.
- Token Evil Teammate: It takes a special level of Jerkass to be this even compared to the rest of ONI.
- Unscrupulous Hero: Look very deep down inside and he actually has a little bit of good left in him.
- We Have Reserves: In his own words, the Spartan-IIIs are meant to "trade lives for time".
- Well-Intentioned Extremist: Does what he has to to keep the Covenant at bay. The events of Halo: Reach would not have happened if werent for him.
Commander Michael "Sully" Sullivan
See the Halo: UNSC page for more details.
Scientists and Researchers
Doctor Catherine Elizabeth Halsey (CC-409871, "Charlie Hotel")
Mastermind of the SPARTAN-II project (building on previous supersoldier projects), Halsey is possibly the most brilliant human alive at the time of the Human-Covenant War. Though frequently clashing with the law in her quest to ensure humanity's survival, she is far from the Well-Intentioned Extremists that make up the rest of ONI, at least in her own opinion.
- Adaptation Dye-Job: Halo Legends and the "Keyes" terminal from Halo: Combat Evolved : Anniversary give her blonde hair, even though the novels and Halo: Reach show that her hair was actually dark before it turned white.
- An Arm and a Leg: At the end of Spartan Ops, Palmer shoots her in the shoulder and the injury leads to Halsey's arm being amputated.
- Becoming the Mask: The beginning of Halo: The Fall of Reach has Keyes and her posing as husband and wife. Guess what happens later.
- Byronic Hero: Intelligent, cultured, cynical, and arrogant, with the willingness to do whatever she believes is necessary regardless of any ethical, political, or legal boundaries in her way, Halsey nonetheless feels personally conflicted about her work.
- The Chessmaster: In Episode 7 of Spartan Ops, she reveals she had a secret override for the Infinity's AI, Roland. Additionally, she had already figured out that Jul 'Mdama had been the one contacting her.
- Defrosting Ice Queen: Is this if you can earn her respect.
- Despite her attempts to maintain a professional distance to her Spartan-IIs, she ends up becoming close to all of them in a pseudo-motherly sort of way.
- She's initially cold and dismissive towards the Spartan-III soldiers, due to her suspicion/misgivings about their origins. She eventually softens considerably - especially towards Noble Six - when she realizes they are quality soldiers who genuinely care for people as well.
- Starts off utterly disdainful of everyone aboard the UNSC Infinity, but eventually comes to regard Spartan-IV Gabriel Throne with a little more respect.
- Despair Event Horizon: Following the Fall of Reach, the discovery of Halo and the Flood, and learning that the Covenant has found Earth, Halsey becomes convinced that the UNSC cannot win the war, and decides to take the Spartan-IIs (and as many Spartan-IIIs as she can) somewhere safe where they can wait out the war. What she failed to realize is how effective a team John and Cortana were. Once she learns how they won the war, she changes her mind and firmly believes he's alive even after he and Cortana have been missing for four years.
- Enemy Mine: 'Mdama manipulates her into secretly helping him, but she eventually figures out who he is. Even afterward, though, she sticks with him because he can help her goals.
- Everyone Has Standards: Despite her For Science! tendencies, she does have her limits; for instance, she encourages John to not give ONI the information about Johnson's potential Flood immunity, since it would likely lead to Johnson being vivisected.
- FaceHeel Turn: While she had been working with the Covenant remnant before, it was only to further humanity's goal of freeing the Librarian. After a botched assassination attempt, though, she apparently joins them for real to get revenge on the UNSC, though it turns out she's not on Jul's side either; in the end, she betrays the Covenant and eventually rejoins the UNSC.
- Fake Defector: As shown at the end of Halo: Escalation, Halsey was never on Jul's side, though the UNSC certainly thought she was. Taken even further in the first level of Halo 5: Guardians, where she sets up Jul's death and is back working for the UNSC for the rest of the game.
- Faking the Dead: ONI declared her KIA during the Fall of Reach (you can even find a memorial with her name on it at the ONI Alpha Site in Halo: ODST. After she was rescued from Onyx, Adm. Parangosky decided to keep it that way, so ONI could continue to make use of her expertise while keeping her on a tight leash out of the public eye.
- First-Name Basis: She always refers to the Spartan-IIs by their names, not their ranks or numbers. During training, John-117 noted that she was the only who called him "John" instead of Trainee-117. After he became known as "Master Chief", she is still the only one to call him "John", as even his close friends on Blue Team still professionally refer to him by his rank.
- For Science!: As she puts it:Halsey: Life is too short. I will never learn all that exists in our own tiny galaxy, let alone the rest of the universe. And I so desperately want to know everything. But the UNSC acts like children at play in a sandbox. Mistaking its edges for the limits of the world.
- Guile Hero: She's perfectly willing to use trickery to get what she wants, and occasionally veers into Manipulative Bastard territory. For example, in Halo: First Strike, she tricks Locklear into helping her escape with a comatose Kelly, and indirectly encourages him to destroy the space-time warping Forerunner crystal, which leads to Locklear's death (though Halsey didn't intend for that last part to happen).
- Headbutting Heroes: The audio logs in Halo 5 show that her and Arbiter Thel 'Vadam do not get along at all.
- HeelFace Revolving Door: During the events of Spartan Ops and Escalation, whether she's on the UNSC's or the Covenant remnant's side depends on which one is currently the most useful to her and which one isn't trying to kill her.
- Hot Scientist: Zigzagged because of her age. Her appearance in the Halo Legends episode "The Package" is played completely straight, and even Halo: Reach and Halo 4 show that age has been rather kind to her. Cortana's looks are partly based on her younger self, and The Fall of Reach describes her as "lovely - not beautiful, but definitely a striking woman" when she was in her twenties, something supported by both of TFoR's visual adaptations.
- Hyper-Awareness: Is very observant. She's able to tell her Spartans apart simply by how they move, she's excellent at figuring out when people are hiding things from her, and she's the only person to realize that Jul 'Mdama's religious fervor is an act.
- Hypocrite: She hates people keeping secrets from her, but when she complains about it in Spartan Ops, a few minutes later she reveals she has hidden override programing that lets her control Roland.
- Insufferable Genius: She's probably the most brilliant scientist alive and she knows it, rubbing it in the faces of everyone in her path when she wants to get her way. While it works for much of her career, the UNSC is far less willing to take it by the time of Halo 4 and Halo 5: Guardians, to the point where they order her assassination after she's captured by 'Mdama's Covenant remnant.Halsey: [while sifting through classified information hidden from her] If people would just share things with me, I could solve all the world's problems.
- I Was Quite a Looker: See above.
- I Did What I Had to Do: Her initial justification for the SPARTAN-II Program.
- Ice Queen: Tends to come off as cold and calculating to most people.
- It's All My Fault: Unspoken but obvious in Halo 5, since Cortana is her Brain Uploading coming back to bite her in the ass. She even says it's her fault in a roundabout way.
- Jerk with a Heart of Gold: Her actions in the Spartan Program and her often cold, dismissive exterior may throw people off, but she is a genuinely caring person struggling with her own morals.
- Kidnapped Scientist: During her incarceration by ONI, she's still called upon to put her scientific talents to use, such as installing the Infinity's Forerunner engines or examining the artifact in Spartan Ops. She's later kidnapped by the Covenant remnant, who want her help in accessing Forerunner technology.
- Laser-Guided Karma: Deliberately invoked by Adm. Parangosky when she's arrested by the UNSC in Halo: Glasslands. Dr. Halsey's death is faked by ONI, and she's put to work on top secret projects like the Infinity without reprieve or parole, not unlike her kidnapping of the Spartan-II candidates decades earlier.
- A Lighter Shade of Black: The SPARTAN-II program is not portrayed at all as a morally-right decision and Halsey's as the head of the project made many grey decisions, but Halsey was well aware of what she had done, truly regretted it despite having gone through with it for the good of humanity, and strived to always do what she could to help the children whose lives she stole from even at her own personal cost. Compare this to much of the rest of ONI, who looked down on Halsey for showing the IIs' so much sentimentality even before she fell out of favor with them and made far worse morally-suspect choices with far less internal angst or questioning.
- Luke, I Am Your Father: With Miranda Keyes being the Luke, as first revealed in her journal.
- Meaningful Name: She shares her name with a character from The Fountainhead.
- Meddling Parents: While she's mostly an aversion, she did initially attempt to use her influence to keep Miranda away from the front-lines, despite her daughter's desire to be directly involved in the fighting.
- Mistreatment-Induced Betrayal: After putting up a truckload of crap for her actions in creating the Spartans, losing an arm to an assassination attempt by ONI via Spartan Palmer seemingly causes her to go over to the Covenant's side. Her reason: "Revenge."
- Moral Luck: A lampshaded case. Halsey tries to justify the fairly heinous acts she committed while training the Spartan IIs by citing the pivotal role they played in the war against the Covenant. Her ONI interrogator calls her on the fact that nobody knew about the Covenant at the time.
- Motherly Scientist: In fact, Parangosky found her relative compassion for the IIs rather exasperating. Her "motherly" instincts are likely a major reason why she becomes especially irritable if someone else tries to claim credit for the Spartan-IIs, as she refers to them as her Spartans. She also feels a strong sense of responsibility for the Spartans-IIIs, despite not being involved in their program.
- My God, What Have I Done?: Eventually, her reaction to the SPARTAN-II Program, though she refuses to admit it to ONI.
- Never My Fault: Invoked. Halsey came to view her actions in the SPARTAN-II Program as terrible before she became willing to publically admit it. This led to situations like in the Halo 4 intro, where she defends and rationalizes her actions to her ONI interrogator, despite agreeing with much of his points in chronologically earlier media.
- Non-Action Guy: Although her many scientific breakthroughs, such as the SPARTAN-II Program and the MJOLNIR armor turned the tide of the Human-Covenant War, she herself is untrained and an overall poor fighter.
- Omnidisciplinary Scientist: Over the course of the series, she's shown herself to be an expert in medical science, artificial intelligence, xenoarchaeology, mechanical engineering, and quantum physics. You name it, she's probably an expert in it.
- Apparently her wish is to know everything there is to learn in the universe. She knows she never will, but she'll try nevertheless.
- Outliving One's Offspring: Does not take Miranda's death well, to say the least.
- Parental Substitute: To the Spartan-IIs, showing legitimate concern for their well-being despite the experimental and excruciating augmentations she placed them through. She also has shades of Parental Favoritism, being especially kind to John. On the other hand, she looks down on the Spartan-IVs, who are essentially mass-production versions of the Spartan-IIs using a mass production version of her MJOLNIR armor.
- Pet the Dog: Halsey expresses her disapproval of the SPARTAN-IV Program, but is slightly more accepting of Gabriel Thorne after seeing his kindness and hearing his backstory.Thorne: So you don't think we're capable of being Spartans.Halsey: Perhaps some of you are closer than others.
- Rapid-Fire Typing: 140 words-per-minute.
- Revenge: Her motivation for her apparent FaceHeel Turn at the end of Spartan Ops, after being shot by Palmer on ONI's orders.
- Silver Vixen: She's still very good looking even at the age of 66 by Halo 5: Guardians. If it weren't for a few scant wrinkles, some undereye bags, and her white hair, she could easily pass for someone twenty years younger.
- Sore Loser: She does not take kindly to being intellectually bested, even at something as simple as a game of Twenty Questions.
- The Stoic: She does her best not to show any emotion...
- Not So Stoic: ... although her POVs show how much emotional turmoil she is really going through and her stoic facade cracks a few times, notably when she learns that Miranda is dead and John-117 is alive, and when she begs Locke to bring John home alive.
- Take the Third Option:
- Have a highly dangerous space-time-bending Forerunner crystal that you don't want in the hands of either the Covenant or ONI? Have an ODST destroy it for you.
- What she tried to do for the Spartans by luring them to Onyx so they can hide out the Human-Covenant War. Unfortunately for her, by that point most of them were either too far into the war or co-opted by ONI.
- Much later, she tries to play the UNSC and Jul's Covenant against each other after the former tries to have her killed.
- Teen Genius: Was working on her second doctoral thesis at age 15.
- Then Let Me Be Evil: After Palmer shoots her near the end of Spartan Ops, she apparently decides that, since the UNSC is trying to straight out have her murdered by a hit squad, she might as well team up with Jul 'Mdama for revenge, though it turns out she really isn't on his side either.
- The Unfettered: Even after her My God, What Have I Done? moment, there is very little she won't do in order to achieve her goals.
- Unscrupulous Hero: Plays a big role in saving the human race... using some rather unsavory means to do so. However, she does hold herself to somewhat higher standards than most of the rest of ONI, and admits to Cortana near the end of the war that she's tired of sacrificing others for the "greater good".
- "Well Done, Mom" Gal: Her strained relationship with her daughter has a few signs of this; Miranda even refused to speak to Halsey for several years, out of resentment over the fact that her mother had been mostly absent from her life since she was six. Halsey herself is perfectly aware that she's not cut out to be a mother, which was the very reason why she let Jacob Keyes handle most of Miranda's upbringing to begin with.
- Well-Intentioned Extremist: Par for the course for ONI members; after all, her first major project involved kidnapping children and turning them into Super Soldiers meant to put down colonial insurrections.
Professor Ellen Anders (CC-500493)
A civilian scientist who is an expert in xenology and a former protégé of Dr. Halsey. She is kidnapped by ONI in 2531 to investigate alien ruins discovered on Harvest during the campaign to retake it, becoming the chief scientist aboard the Spirit of Fire.
- Belligerent Sexual Tension: With Forge. They may bicker constantly, but Anders clearly cares for his well-being, to the point where she surrenders herself to the Arbiter on the condition that he spares Forge's life.
- Brainy Brunette
- Catchphrase: "Nothing ventured, nothing gained."
- Distressed Damsel: Thanks to Ripa 'Moramee.
- Damsel out of Distress: Manages to escape from the Covenant on her own, though she still needs Forge's help to get away from the Flood.
- Deliberately Distressed Damsel: Possibly; her transponder signal is what leads the Spirit of Fire to Shield World 0459 in the first place, and the information she gains from her captivity is why UNSC forces are able to foil the Covenant's plans to use the Shield World's cache of Forerunner ships.
- Doomed Hometown: Arcadia, which gets invaded during the events of Halo Wars.
- Heroic Sacrifice: Played with; she comes up with the plan to use the Spirit of Fire's slipspace engine to destroy Shield World 0459 to deny the Covenant use of its Forerunner fleet, despite this effectively dooming her and the rest of the crew to being stranded in space. However, she ultimately survives the experience.
- Hot Scientist
- Ink-Suit Actor: In Halo Wars 2.
- Kidnapped Scientist: Twice, really. The first was by ONI, who forced her onto the mission to Harvest. The second was by Ripa 'Moramee, who captures her so that the Prophet of Regret can use her to access the shield world's Forerunner fleet.
- Legally Dead: The UNSC officially considers the Spirit of Fire "lost with all hands".
- Number Two: Though her official designation is only "civilian consultant", she's the de-facto right hand of Captain Cutter by the time of Halo Wars 2.
- Omnidisciplinary Scientist: Due to her interest in all things alien, she's an expert in various subjects ranging from biopsychology to high-energy physics.
- Out of the Frying Pan: Anders escaped the Ark at the at of Halo Wars 2 on a Halo ring in order call for help to fight against the Banished, only to encounter Cortana's Guardians along the way.
- Rage Against the Mentor: Has expressed her hatred of Catherine Halsey, whom she studied under, on several occasions.
- The Smart Girl: For the Spirit of Fire's crew, as their main scientist.
Doctor Sandra K. Tillson (CC-728304)
An archeologist stationed on Ivanoff Station in orbit of Installation 03, Tillson is the head of ONI's research projects into Forerunner technology recovered from the Halo ring.
- Fate Worse than Death: She gets killed by the Composer and her remains are harvested to create Promeatheans.
- For Science!: Downplayed. She initially objects to John destroying more Forerunner artifacts that are too dangerous to keep around, but reluctantly decides it's for the best.
- Good Counterpart / Suspiciously Similar Substitute: To Dr. Halsey.
- Mauve Shirt: Appears in one level of Halo 4 before being killed off, although she has significant screentime during that level.
- Younger Than They Look: She's only 51 but looks a lot older.
Doctor Henry Glassman (CC-652562)
A former researcher for ONI's Beta-5 Division, and current chief engineer and scientist aboard the UNSC Infinity, he assisted Dr. Catherine Halsey in installing the Forerunner technology into the Infinity's engines and helped investigate Forerunner technology during its mission to Requiem.
- Curious as a Monkey: Doctor Halsey implies that his messing with the Forerunner artifact in Episode 2 of Spartan Ops (which teleports him to straight to the Covenant remnant's main base on Requiem) is not an unusual action for him, which is precisely why she considers him a fool.
- Distressed Dude: Captive of the Covenant Remnant as of Episode 3 of Spartan Ops. He manages to escape in Episode 6.
- 11th-Hour Ranger: For Crimson's support staff.
- Explosive Leash: Jul forces him to wear an explosive vest, complete with Slave Collar (with Gek holding the leash). Fortunately, Thorne is able to rip it off and toss it away before Gek can detonate it.
- For Science!: Despite being a captive, he seems legitimately interested in the Forerunner technology that Jul 'Mdama is forcing him to work on. He even cheers when he makes a breakthrough in activating the device.
- Kidnapped Scientist: Jul 'Mdama seeks to use his knowledge to access Forerunner technology.
- Mission Control: Provides some direct technical support for Crimson towards the end of Spartan Ops.
- Nerd Glasses: A textbook example of a bespectacled Non-Action Guy scientist.
- Teeth-Clenched Teamwork: Implied with Halsey. In Episode 2, he refers to Halsey as a war criminal, and in Episode 3, she implies she doesn't think much of him either.
Professor Evan Phillips
Phillips is a human cultural xenoanthropologist distinguished as being a highly fluent speaker of the Sangheili language, he was recruited by ONI to join Kilo-Five after the war against the Covenant.
- Cunning Linguist: Also has some fluency in Kig-Yar tongues.
- Naïve Newcomer: Averted, for the most part: the other members of Kilo-Five expect him to be this, but he is actually fine with screwing over the Sangheili despite his respect for the culture and the Arbiter, reasoning that there is too much bad blood between the two species. He does get a little freaked out by other aspects of ONI though, and after seeing the results of ONI's policy towards the Sangheili first hand, he feels guilt over his part in causing the civil war and comes to think that peace is possible.
- Non-Action Guy
- Action Survivor: Mildly; when he's trapped in Nes'alun Keep while it's being besieged by its rivals, its acting mistress Elar 'Nas hands him a plasma pistol and has him take part in the defense.
- Ship Tease: With ODST Lian Devereaux, which the other two ODSTs in Kilo-Five are not blind to (and indeed seem to encourage).
- The Smart Guy: Shares the role with Black-Box in Kilo-Five, but only in dealings with the ex-Covenant races.
- Stock Lateral Thinking Puzzle: He can solve any Arum (a Sangheili mental puzzle) in under an hour. When an Elite asks him if all humans can do this, he says that it is unlikely. The Elite is relieved, as a yes answer would have meant humans were more dangerous than they realized.
- Token Good Teammate: The only member of Kilo-Five who sees the Sangheili as anything other than targets to be killed, and the only one who feels any grief for the Sangheili civilians and children killed in the civil war on Sanghelios.
- Tragic Keepsake: The plasma pistol given to him by Elar 'Nas, whose death (and those of the rest of the women and children of Nes'alun Keep) he feels could have been averted had Kilo-Five stayed to help them.
Captain Veronica Ann Dare (73998-38490-VD)
A ONI Intelligence Officer assigned to the UNSC Say My Name, Dare used to be in a relationship with ODST Sergeant Edward Buck, but broke it off with him after he proposed. When Earth is invaded by the Covenant, she selects Buck and his squad Alpha-Nine to assist her in securing a high value asset in New Mombasa.
- Action Girl: More so than Miranda Keyes, who serves in a primarily command-based role.
- Badass Normal: Survives largely on her own for much of the New Mombasa battle.
- The Captain: Though Buck is the one that Alpha-Nine actually listens to.
- Disney Death: She's thought to be dead by the squad after regrouping, but then Buck has a "Eureka!" Moment that lets him guess where she is.
- Helmets Are Hardly Heroic: She fights without a helmet, but not by choice. Her helmet was stolen and destroyed during the second level.
- Informed Attractiveness: Romeo greets her with "Hello, beautiful", but then backs off when he finds out she's now leading their squad. By the end of the game he hates her enough to ask why they bothered retrieving her before escaping.
- Ink Suit Actress
- Jerk With A Heartof Gold: When she radios for a status check, the first one she asks after is Buck. It is clear from her tone she is worried about him and only goes back to being cold when he gives a sarcastic affirmative.
- Mission Control: Is often Buck's mission handler, even after he becomes a Spartan.
- Obstructive Bureaucrat: In a weird way, she's a benevolent one. Upon arriving she takes command of Buck's squad and cancels their participation in the op to hijack a Covenant carrier. The whole squad is ticked, but ironically this change of mission ends up saving their lives. She's only obstructive in that she doesn't bother to tell her team what the new objective is.
- Official Couple: With Buck after the end of Halo 3: ODST, though the nature of both their jobs means that they have absolutely no plans to marry and have kids anytime soon.
- Slap-Slap-Kiss: Ouch!! ...awww.
- Tsundere: Towards Buck, as a Type A. It's particularly apparent in ODST, where she's still keeping her distance with him because she has work to do, while Buck was still bitter toward her because she wouldn't answer his marriage proposal. She shows more of her deredere side in Halo: New Blood, where the two have long since worked out most of their issues with each other.
- Working with the Ex: With Buck for most of ODST, though the "ex" part is gone by the end.
Lieutenant Michael Bradley Horrigan
Born to a prominent political family, Horrigan rejected a civil service career in favor of a military one, believing that doing so would allow him to earn his place without relying on his parents' influence. In 2556, he serves as an ONI field operative under Jameson Locke's command.
- Asshole Victim: Given how much of a selfish jerk he is, it's hard to feel sorry for him once the Thanolekgolo finally get him.
- Bad Guys Do the Dirty Work: His betrayal and constant team-killing greatly simplifies Halo: Nightfall's Drawing Straws dilemma by leaving the "good guy" party with only three people, allowing them to only have to deliberately leave behind one person.
- Eaten Alive: By Lekgolo worms, just meters away from the escape vessel.
- Dirty Coward: Despite his bravado, the Alpha Shard mission reveals him to be this at heart.
- FaceHeel Turn: Hes not really a "good" guy to begin with, but he goes from being a proud ONI agent to someone who unhesitatingly abandons his mission and betrays his comrades just to save himself.
- Jerkass: Makes no secret of his sheer disdain for the Sedrans. And that's not getting into him betraying everyone else just to save his own skin.
- The Lancer: Has this dynamic with Locke, being the less diplomatic and more ruthless of the two.
- Number Two: Is implied to be this to Locke, having served with him the longest out of his entire ONI squad.
- Pride: Considers ONI to be humanity's best shot for putting itself back together in the post-war era, to the point where he looks down on anyone who isn't UNSC.
- Shoot the Dog: How he views sacrificing Haisal to the Lekgolo to give everyone else time to escape, given that Haisal had a broken leg and was partly responsible for the bioweapon attack on Sedra City to begin with. Locke vehemently disagrees.
- Smug Snake: Takes whatever opportunity he can to deride the Sedrans' professional competence, but he ends up being the first to contemplate betrayal during the Alpha Shard mission.
- Team Killer: Apart from killing both of the Alerians, he also betrays fellow traitor Ramos by turning on his backpack's electronics and knocking him down to ensure the pursuing Lekgolo will go after him first.
- We Used to Be Friends: Seems to have been personally offended by Locke rejecting his offer to join him in betraying everyone else on the Alpha Shard.
Warrant Officer Gregory Aio Ramos
Joining ONI primarily because it promised long-term advancement and the flexibility to see his family often, Ramos is the medic for Jameson Locke's unit in 2556. His long-term goal is to get a stable post where he can be with his family more regularly.
- Doting Parent: Implied to be this to his children.
- Eaten Alive: By the Thanolekgolo.
- Face Death with Dignity: He resigns himself to death once it's clear he can't outrun the Lekgolo, and does his best not to scream in pain until he finally can't hold it in.
- FaceHeel Turn: Joins Horrigan's mutiny against Locke.
- Fatal Family Photo: A straight example; he keeps recordings of his children with him on all his missions, though he does manage to survive all the way to Halo: Nightfall's last episode before finally biting it.
- Freak Out: Becomes visibly distressed and panicky after witnessing Wisner get eaten by Lekgolo, which leads to his FaceHeel Turn.
- Former Teen Rebel: Had a hard time keeping a job in his late teens and early twenties thanks to a self-centered attitude, but changed after marrying and having kids.
- Karmic Death: Betrays Locke to save himself, but ends up dying when fellow traitor Horrigan saves himself by turning on Ramos's electronic backpack and knocking him down so that the pursuing Lekgolo will go for him first.
- Love Makes You Evil: His main motivation for joining Horrigan's mutiny is his worry that no one will take care of his family if he dies, and he rationalizes his betrayal by noting that no one else on the squad has kids to take care of.
- The Medic: For Lockes squad in Halo: Nightfall, though circumstances on the Alpha Shard don't really allow him to put those skills to good use.
- Rewarded as a Traitor Deserves: Joins Horrigan's mutiny against Locke, but ends up being betrayed himself by Horrigan.
- Team Killer: He lets Estrin fall to his death after the latter refuses to conspire with him in betraying the rest of the squad.
- The Unfettered: Ultimately, the main thing that matters to him is his family, even over his comrades.
Petty Officer Second Class Alistair Bov Estrin
Having grown up dreaming about fighting against the Covenant, Estrin was disappointed when the war ended right as he became old enough to serve. Nonetheless, he unhesitatingly signed up with ONI, and is the youngest member of Jameson Locke's team in 2556.
- Deadpan Snarker: Possibly the most sarcastic of Locke's team.
- Disney Villain Death: Though hes not a villain in any way, Estrin does end up falling to his death after Ramos refuses to pull him up.
- In Harm's Way: Joined ONI because it offered the most dangerous and unpredictable assignments.
- Naïve Newcomer: His Waypoint profile even states that he also joined ONI because the idea of being a "secret agent" appealed to him.
- Token Good Teammate: The only member of Locke's squad to not betray him during the Alpha Shard mission.
- Undying Loyalty: Even as things get worse and worse on the Alpha Shard, he stays loyal to both Locke and the mission. It gets him killed when he refuses to conspire with Ramos to betray everyone else.
Lieutenant Elias Haverson
An ONI officer assigned to the UNSC Pillar of Autumn, and one of the few survivors of Alpha Halo.
- Dirty Business: His execution of an Engineer who worked on the Master Chief's armor, since he couldn't take the risk of the Covenant recapturing it and learning about the improvements the UNSC had made to their shielding technology. He's disgusted with himself afterwards, but believes that it was the right thing to do.
- Heroic Sacrifice/Dying Moment of Awesome: He and Admiral Whitcomb crash the Ascendant Justice into the just-about-to-self-destruct Unyielding Hierophant, using a Forerunner artifact to lure in a Covenant fleet of over 500 ships. When the station explodes, only twelve Covenant ships survive.
- Hidden Depths: Initially comes across as your typical untrustworthy heartless ONI bastard, but we soon learn that he does have both a heart and genuine bravery. He also legitimately sympathizes with the Chief's desire to make sure his Spartans are alive.
- Pragmatic Hero: As noted in Dirty Business, he's willing to take unpleasant measures in the interest of the greater good. Despite his Hidden Depths, this can even border on Unscrupulous Hero territory; for this reason, Halsey doesn't trust Haverson with either the information about Johnson's potential Flood immunity (because it would lead to the Sergeant's death) or the mysterious Forerunner crystal (because he'd be willing to sacrifice everyone aboard the Gettysburg-Ascendant Justice to get it to ONI).
- Reasonable Authority Figure: Despite outranking the Master Chief, he willingly concedes command of the mission to capture the Ascendant Justice to the Spartan. Even after he retakes command, Haverson still agrees to take the crew back to Reach even though he knows that the Master Chief really only wants to go there to check for surviving Spartans (though Haverson himself has more pragmatic reasons for agreeing to the request).
Lieutenant Commander Jilan al-Cygni
An ONI agent assigned to investigate possible Insurrectionist activity near Harvest in 2525, with the help of Staff Sergeants Avery Johnson and Nolan Byrne. She instead discovers the approaching forces of the Covenant.
- Action Girl: Ends up taking part in the fighting on Harvest.
- Ambiguously Brown: Described as being just a few shades lighter than brown; it's implied she's of Arabic descent.
- The Chains of Commanding: She can be quite harsh and ruthless in the pursuit of her duties, but it's clear at the end that she's genuinely upset about all the people who died on Harvest, and clearly wishes she could have saved all of them.
- Defrosting Ice Queen: She softens towards Johnson over the course of the fighting on Harvest, allowing herself to be vulnerable around him; he knows what the ladies like, after all.
- Hyper-Awareness: Is able to quickly notice that the AIs Mack and Sif are having a private conversation in code when the latter is just a few seconds late in responding to one of her queries.
- Silk Hiding Steel: A woman who's not to be messed with despite her slender frame and outwardly polite demeanor; Johnson describes her as being beautiful in the same way a well-maintained weapon is - "clean, locked tight, and ready to inflict deadly force". As such, she's more than capable of casually threatening a hardened Marine while in an elegant ballroom dress.
- Mysterious Past: Even after defrosting a bit by the end of Halo: Contact Harvest, her past remains a near-total mystery.
- Not So Stoic: Her placid facade starts to show a few cracks once the Covenant show up.
- She Cleans Up Nicely: We first see her in disguise, where she's described as looking like a typical DCS middle manager. At Harvest's Solstice Celebration, she wears a fashionable backless silver dress that has her stunning even Johnson.
- What Happened to the Mouse?: At the end of Halo: Contact Harvest, she and Johnson have become fairly close, but there's been no mention of her since.
- Wolf in Sheep's Clothing: More than capable of presenting a pleasant, smiling demeanor, but is cold and ruthless underneath.
Major Akio Watanabe
A Marine officer and member of the ONI Prowler Corps assigned to the UNSC Midsummer Night in 2535 to help enforce the newly enacted Cole Protocol. He is widely mistrusted by the crew due to his ONI status and cold nature.
- Character Death: Courtesy of the insurgents on Charybdis IX.
- Cold-Blooded Torture: He suffered it at the hands of Insurrectionists, leaving him with scars all over his body before being rescued by the ONI Prowler Corps. He refutes the idea that Torture Always Works, claiming that people would say anything, and even believe it was true, just to make it stop. Because of his experiences, he refuses to employ torture. ONI as a whole, however...not so much.
- Covered with Scars: See above.
- The Cynic: He believes that human nature led to the rise of the Insurrection, and that humans will always fight and divide themselves into factions.
- I Owe You My Life: Is utterly loyal to the Prowler Corps due to them saving his life.
- I Take Offense to That Last One!: He's strongly offended when one of the Midsummer Night's bridge officers believe he's torturing an Insurrectionist prisoner.
- Loners Are Freaks: What the rest of the crew thinks of him.
- Majorly Awesome: Can more than hold his own in a firefight; Kincaide is only able to kill him by shooting through a fellow rebel.
- The Stoic: To the point of utter coldness.
- The Spook: Remains mostly an enigma to the very end.
A senior ONI agent in Section III with oversight of a number of other agents and projects. SURGEON's identity is completely unknown.
- Ascended Extra: Originally just a passing reference from an ONI document in Halo: The Fall of Reach, SURGEON went on to be the fandom's source of ONI information during the Bungie-era. SURGEON retains the job in the 343-era.
- Enigmatic Minion: Nothing is known about SURGEON. Name, gender, race. You name it, we don't know about it.
- Narrator: Serves as the narrator for The Impossible Life and Possible Death of Preston J. Cole in Halo: Evolutions.
- The Spymaster: SURGEON seems to have their hands in everything Section III has going on at any given time. Operation: HYPODERMIC, the SPARTAN-III program, post-war assessment on the Covenant remnants. You name it, SURGEON is aware of it. Something of an accomplishment in the Parangosky/Osman-era.
A Sangheili with an inclination for deception and self-preservation, Ayit is ONI's go-to agent whenever a Covenant faction needs to be infiltrated.
- Consummate Professional: Ayit's mission-focused mindset allows him to completely put aside all personal issues whenever he has work to do.
- Hyper-Competent Sidekick: Is this for his human teammates during Operation: ATHENA.
- Manipulative Bastard: As befitting of an ONI agent; he takes advantage of the Covenant remnant's lingering mistrust towards Jul 'Mdama to successfully instigate a large-scale mutiny, and plays Sali 'Nyon like a harp by appealing to his religious fervor.
- My Species Doth Protest Too Much: Praised by Osman for having an unusual instinct for self-preservation and deception as well as having no allegiances or loyalties to any Sangheili faction. In short, the most human Sangheili that ONI could find.
- Nominal Hero: Is seemingly uninterested in any sort of greater cause.
- Only in It for the Money: Has no real stake in helping humanity outside of ONI being his paymasters.
- Opportunistic Bastard: Can give Jul 'Mdama a run for his money; he uses rebel prisoner Sali 'Nyon's sudden transfer to the Breath of Annihilation, Jul denying the rumors of Spartans aboard said ship, and the chaos caused by the destructive effects of the Absolute Record's portal to successfully instigate a mutiny against Jul aboard the Breath of Annihilation.
- The Mole: Infiltrates Jul 'Mdama's faction on ONI's behalf.
- Teeth-Clenched Teamwork: With Thorne on Operation: ATHENA, thanks to Ayit once capturing and selling him to Jackal pirates as part of his cover on a previous mission. It's mostly on Thorne's end, due to Ayit's professionalism.
- Token Non-Human: The only Sangheili solely on ONI's payroll.
- Xanatos Speed Chess: Part-and-parcel of being an ONI field agent; when Operation: ATHENA is about to go FUBAR, Ayit's the one who saves the mission by coming up with a new plan.
Lieutenant Commander Fhajad
See "Fhajad-084" on the Halo: SPARTAN-II Program page for more details.
Lieutenant Commander Jameson Locke
See the Halo: SPARTAN-IV Program page for more details.
See the Halo: SPARTAN-IV Program page for more details.
See the Halo: UEG Civilians page for more details.