Both Earth and Luna (the Moon) are controlled by the United Nations, still headquartered in New York City.
Things aren't great on Earth in some respects. They have some pollution/global warming problems, so that the sea levels are noticeably higher (big dams keep the oceans from flooding NYC). The space colonists deride Earthers for paving over paradise, badly polluting the only truly habitable planet in the solar system. The Martians deride Earther culture as bloated, corrupt, and everyone looking for a government handout because Earth's industries can't employ and feed all of its vast population.
- Big Applesauce: The United Nations is the global government for Earth now (including the Luna colonies), and United Nations headquarters is still located in New York City. Thus, most of the scenes actually showing Earth tend to take place around NYC — though the future cityscape has dramatically altered, with huge dams holding back the sea levels that rose due to global warming.
- Break Out the Museum Piece: As the war with Mars rages on, the UN is forced to pull its older vessels out of mothballs to replace their substantial losses. This actually serves them well, as the older Truman-class is far better at going toe to toe with modern Martian vessels than any modern UN warship, a side effect of not being engineered by a committee.
- Crapsack World: Overpopulation and uncontrolled pollution have wreaked havoc on Earth.
- Sea levels have risen significantly due to climate change, limiting the amount of land that can be farmed and developed. What remains has been mostly been built over. There are small pockets of land being fiercely held by their owners (like Jim Holden's family) as the government tries everything to seize them.
- There are not enough jobs to go around so everyone receives some sort of government assistance. Being knocked down to Basic Assistance is a terrifying possibility for most people because it means living on the streets sometimes exposed to hazards like dangerous levels of radiation, lack of clean water, etc. with no accessible medical treatment. Such people have to scrounge and scavenge scraps to supplement what little is provided by the government even if it means having to drink sewer water to survive. And even with government subsidies, there is no guarantee that the people will get what they need because what is included in the packages can be changed without the people being able to do anything about it.
- It turns out that theres also quite a large population of the "undocumented" on Earth who get no assistance whatsoever from the government and cant even dream of getting a real job. Annas church runs a charity clinic that offers care to the undocumented.
- Even education and vocational training is rationed and given only to those who have connections and are sponsored or the lucky few who are selected via lottery.Niko: I put myself on the vocational training list when I was 17 years old. I'm 52 now. Still waiting for my slot.
- Amos' describing his upbringing (in the slums of Baltimore) to Prax Ming brings to light just how rough some parts of Earth have become.Amos: Where I come from bullies take desperate young girls like your daughter and force them into prostitution. And when they finally get knocked up...they peddle them to johns who get off on that. After they have the kid, they push them right back out onto the streets before they have a chance to heal. And those kids? They use them, too.
- Crapsack Only by Comparison: But even with all this, Earth is still considered a paradise next to living in space stations in the Asteroid Belt, where air and water are worth more than gold, and Martians consider Earthers to be pampered and soft. Better medical technology is also readily available: amputated limbs can be grown back witha special gel and a coroner on Ceres mentions that the average life expectancy on Earth is 123 years, and it's even better on Mars, but the average life expectancy in the Belt is only 68. Damaged environment or not, Earth still supports agriculture to produce real meat, real fruit, real vegetables, and real dairy products, instead of having to rely on soy-based substitutes.
- Darker and Edgier: Life on Earth is portrayed as much nastier, and the government more dysfunctional, in the series than in the books.
- Earth That Was: ...Not quite that bad yet, but Mars accuses that Earth is so badly polluted and overpopulated that it's on its way to becoming this — so the best chance for the human race is to just give up on Earth as a lost cause and terraform Mars. Most of Earth's natural resources have been maxed out too, so like Mars it gets raw materials by exploiting the asteroid belt.
- Gaia's Lament: Not nearly as bad as many other examples, as there's still enough clean water, air, and food to go around, and the view from orbit seems to indicate that there are still significant wilderness areas. Still, centuries of pollution and overpopulation have taxed Earth's resources to the limit. Sea levels have risen dramatically, and the coastal cities that have survived (such as New York and Copenhagen) must be protected by massive sea walls. Good agricultural land is apparently at a premium, as the intense government efforts to acquire the Holden family farm show. It's mentioned that many of the rivers and coasts reek of sewage.
- Heavy Worlder: Simply because no other colonized celestial body has stronger gravity. Earthers are denser and stronger relative to the Belters, and to a lesser extent the Martians. The tradeoff is that Earthers consume more oxygen than Martians or Belters.
- Julie Mao, a fit, if petite, young woman, easily manhandled three burly Belter men who accosted her.
- Quantity vs. Quality: Balanced against Mars. The ships of the UN are far more numerous than those of the MCRN, and unlike Mars they can also draw on mothballed reserves. However, their fleets are composed of markedly inferior vessels than those of Mars. Supplementary material states that their most modern warship, the Leonidas-class, is an overengineered Master of None whose production history resembles the Bradley IFV in space, and the closest thing to an even fight they can bring to the Martians is decades out of date. Within weeks of engaging in war with Mars, their numbers advantage has dwindled from 5-to-1 to 3-to-1. However, this policy of throwing cheaply engineered vessels does ultimately pay off for them, as by that same time the Martians are becoming exhausted, while the UN is still able to mobilize "new" units.
- Space Navy: The United Nations Navy, or UNN. They have a numerical advantage over their Martian counterpart, the MCRN, but their ships are far inferior (see Quantity vs. Quality above).
- United Nations Is a Superpower: The UN is now the unified, democratic government of Earth and Luna. At the start of the series, they nominally hold authority over the asteroid belt and outer planets colonies as well, but the OPA rebels/terrorists disagree.
United Nations Government
His Excellency, Secretary-General Esteban Sorrento-Gillis is the head of state and head of government of the United Nations, one of the two human superpowers and the original human unified nation. Because of his premier position within the UN government, he is arguably the most powerful human.
Sorrento-Gillis is the executive head of the UNSC, being responsible of nearly all interactions between the Earth-based nations and all foreign sovereignties.
- Ambition Is Evil: Sorrento-Gillis is obsessed with his own historical legacy to the detriment of everything else. Anna sees his ambition as the greatest obstacle to him becoming a halfway decent leader, and Errinwright knows that playing on Sorrento-Gillis' desire to be an important historical figure is the quickest and easiest way to manipulate him.
- Cultured Warrior: Played with and ultimately subverted and deconstructed. He doesn't want to be a warrior and often finds himself quoting poetry and literature in the face of conflict. Ultimately, all his quoting just exposes that Sorrento-Gillis is only good at repeating what he's been told, rather than really understanding it.
- Hero with Bad Publicity: Initially the case. This changes after a Martian nuke kills two million people in South America; his subsequent speech written by Anna (and edited liberally by Errinwright) swiftly unifies the population of Earth behind him and against the MCR.
- It's All About Me: To Anna's (and the audience's) increasing horror, it becomes clear that Sorrento-Gillis thinks only of himself and his legacy. After he arrests Errinwright, he confirms everything Sadavir said moments before by thanking Anna not for bringing a dangerously corrupt politician to justice and thus potentially saving billions of lives, but for safeguarding his own legacy. The look of utter shock and despair on Anna's face says it all.Errinwright: He doesn't care about treason. That's just him parroting [Anna] because you talked to him last. If he spoke to a janitor, he'd be passionately declaiming about a fucking mop. It's agonizing. I've lost count of how many times I stopped him from blundering into political suicide. And now, we have a chance to assure the future of the Earth, and he's shitting himself because he's afraid the history books won't be flattering enough.
[literal seconds later]
Sorrento-Gillis: [relived] My legacy was going to be a catastrophic war with millions dead. That's all on Errinwright now.
- Puppet King: Avasarala and Errinwright figured out a long time ago that he is, in Avasarala's words, "a bobblehead." He's easily flattered and manipulated by people with more conviction. This comes into crystal focus during the Eros crisis, as he babbles poetry in the war room and is easily swayed into rubber-stamping the actual decisions made by Errinwright and then Avasarala.
- Put on a Bus: He resigns in the aftermath of the Earth-Mars war, with Avasarala taking his place as Secretary-General.
- Reluctant Warrior: He's extremely reluctant to go to war, and it takes some convincing and a lot of incidents piling up to finally push him into it.
The UN Deputy Undersecretary of Executive Administration — third in line from the UN Secretary-General (and from being leader of the Earth and Luna). She takes a very active role in protecting the interests of Earth and Luna, intent on making sure that the United Nations remains the dominant power in the Solar System.
- Adaptational Angst Upgrade: In the books, her son was simply killed in a skiing accident. However, in the show he was a UNN soldier killed by the OPA, giving her both an It's Personal interest in the OPA and an Adult Fear understanding that War Is Hell.
- Adaptational Early Appearance: Doesn't appear until the second book but is a major character from the first episode of the series.
- Adaptational Nice Guy: Heavily downplayed, but her more abrasive Screw Politeness, I'm a Senior! and Sir Swears-a-Lot traits aren't as apparent here as they are in her book counterpart.
- Adaptational Villainy: Has no problems overseeing torture sessions personally.
- Adrenaline Makeover: The events aboard Jules-Pierre Mao's yacht at the beginning of Season 3 leave Avasarala's normally impeccable clothes and hairdo in shambles. She does manage to fix the latter (somehow) during the desperate flight aboard the Razorback, though.
- Anti-Hero: While she is absolutely ruthless, she has genuinely benevolent goals and is one of the few members of Earth's or any other government trying to maintain peace in the Solar System rather than engage in power plays or conspiracies that jeopardize said peace.
- Badass Boast: Her epic warning to the Mao family (which also counts as a veiled threat to Errinwright about her knowing that he's part of The Conspiracy):"And please let them know that if they can't [persuade Jules-Pierre Mao to turn himself in], I will rain hellfire down on them all. I will freeze their assets. Cancel their contracts. Cripple their business. And I have the power to do it, because I am the fucking hero who helped save Mother Earth from the cataclysm that Jules-Pierre Mao unleashed. Tell his children that government is more powerful than any corporation and the only reason they think it tilts the other way is because we poor, public servants are always looking for some fat private sector payoffs down the road. But I'm not looking. And by the time they pull the strings to force me out, it'll be too late. Their family will be ruined. Their mother, the children, their children, all of them. Pariahs! Outlaws! Hunted and on the run for the rest of their days until we find them and nail each and every last one to the wall! Make sure you tell them that."
- Berserk Button: Don't call her old. Or comment on her age in any capacity for that matter. Well, unless you're Cotyar.
- Big Good: After becoming the UN Secretary-General in "Delta-V".
- The Chessmaster: She knows how to manipulate those around her in order to gain the necessary intelligence.
- Deadpan Snarker: Sports a wit drier than the Sahara.
- Demoted to Extra: She doesn't play an active role throughout the second half of Season 3. Justified since most of it takes place in the "Slow Zone" while she's on Earth.
- Disproportionate Retribution: When she goes after Mao, she goes all the way. From freezing all of his accounts, to arresting virtually every member of his family, nothing is off the books. She even arrests his cousin, a Buddhist monk.
- Establishing Character Moment: Her introduction shows her happily playing along with her grandson's childish antics, followed by her immediately being called away to oversee Cold-Blooded Torture. This quickly communicates her extreme duality as a genuinely good-hearted person who is nonetheless willing to tread dangerously close to the Moral Event Horizon for the sake of her cause.
- Everyone Has Standards: While she shows a clear disdain for Mars (largely in part to them being a Rising Empire in opposition to Earth), she's still horrified by the planned Final Solution against the Martian Congressional Republic by Nguyen.
- Gone Horribly Right: She taught Errinwright everything he knows - from political tactics, to his fiercely nationalistic attitude. Needless to say, this nearly got her killed several times over.
- Good Is Not Nice: For a given value of good, anyway. She's one of the few people who genuinely care about preventing war, but her methods are morally questionable on a good day.
- Guttural Growler: She has a deep, sultry voice.
- Happily Married: Chrisjen's husband Arjun is a loyal and loving partner up until her reelection campaign in Season 4. Arjun sees some of her more ruthless decisions first-hand and decides she's crossed the Moral Event Horizon, doing serious damage to their relationship. In retrospect, it's telling that Chrisjen sends her husband away during crises. Ostensibly, it's for his safety — but it also gets him out of the picture when she might have to make choices that would disappoint him.
- Intergenerational Friendship: With Bobbie Draper.
- It's Personal: When Sadavir asks if she's taking her investigation into the OPA personally due to them causing the death of her son, she makes it clear that yes, damn right it's personal.
- Jack Bauer Interrogation Technique: She's willing to use gravity torture on a Belter despite the UN officially opposing such techniques.
- Jerk with a Heart of Gold: Well, more silver than gold, but for all of her Screw Politeness, I'm a Senior! moments, she's genuinely dedicated to helping bring about prosperity and preventing war throughout the Solar System, and does this all without trying to kill countless innocent people.
- Manipulative Bitch: Definitely counts as one, and cheerfully lampshades it, too.Avasarala: I'm a smug old bitch who enjoys playing with life and death with a big chessboard; a snake in a sari...
- Never Mess with Granny: Chrisjen is a seriously formidable senior citizen. She's highly intelligent, dangerously insightful, an expert manipulator, and has Nerves of Steel that would put hardened soldiers to shame.
- Non-Idle Rich: She lives in a large house with plenty of green space, a sign of ostentatious wealth in a world that is almost completely built over. However, she still puts in grueling hours at the UN to make sure that Earth remains the system's dominant power.
- Obfuscating Stupidity: She spends a while pretending to be completely oblivious to Errinwright's alliance with Mao, all the while biding her time to nail them both.
- Odd Friendship: Develops this kind of dynamic with Bobbie Draper during Seasons 2 & 3.
- Only Sane Man: She often comes across as one of the only members of the United Nations Security Council who actually has her head screwed on straight.
- Pet the Dog: Absolutely dotes on her grandson.
- Pimped-Out Dress: Chrisjen wears saris, and they are always covered with gold embroidery and jewels.
- Precision F-Strike: Beginning in Season 2 she starts landing the occasional F-strike when she gets revved up and is about to rain hell upon those who've crossed Earth.
- Rank Up:
- After Errinwright is arrested and Sorrento-Gillis resigns, she becomes the Secretary-General of the United Nations in "Delta-V".
- She gets another one when an asteroid kills Secretary General Gao and half her cabinet, leaving the unprepared Transportation Secretary in charge. After his cabinet removes him with a vote of no confidence, Avasarala once again finds herself leading Earth.
- Reassigned to Antarctica: After she loses the election for Secretary General to her opponent Nancy Gao, the latter has her reassigned to the Lunar colony out of spite. It proves to be a blessing in disguise for her when Earth is hit with several asteroid attacks by the Free Navy. If Gao had kept her in her inner circle, she almost certainly would have been killed along with the rest of the cabinet.
- Reasonable Authority Figure: Her number-one concern is maintaining peace and stability throughout the Solar System.
- Resign in Protest: In the fifth season, after doing everything in her power to turn the new UN Secretary General David Paster away from indiscriminate war with the Belt and targeting Belter civilians, only to be ignored out of hand, Avasarala resigns on the spot in the middle of a cabinet meeting. It inspires a wave of further such resignations and winds up bringing down Paster, as he quickly falls to a no confidence vote.
- Screw Politeness, I'm a Senior!: Downplayed in comparison to her novel counterpart, but she still gets a few barbs in when it comes to telling people what she thinks of them.Jules-Pierre Mao: Madame Under-Secretary, I appreciate you coming-
Chrisjen: Just get to the fucking point!
- Screw the Money, I Have Rules!: As she pointedly tells Errinwright, she works for Earth, and won't be bought off by a businessman like Mao trying to buy her loyalty through campaign donations and other favors. She also has no problem using every legal tool available to her to ruin Mao's life and that of his entire family to force him to come to justice.
- Sir Swears-a-Lot: Also downplayed compared to the books, but she still says what she can get away with more than everyone else without the show moving to HBO or Showtime. This is lampshaded by Holden in Season 3, who notes that she swears like a sailor even though she hates space.
- Silver Fox: Amos definitely appreciates her.Amos: How did she look?
Holden: She looked fine.
Amos: No, I mean, what was she wearing?
Holden: ...it's good to be back.
- Teeth-Clenched Teamwork: With the crew of the Rocinante throughout most of the first half of Season 3, though it's particularly obvious in regards to her interactions with Naomi.
- Undying Loyalty: To the Earth itself (and, by extension, the UN). One of her most common turns of phrase is a simple "Earth must come first."
- Vitriolic Best Buds: Has this dynamic with Cotyar. They pretty much hate each other and will never miss an opportunity to feed unfiltered shit to the other, and yet have Undying Loyalty to one another as well. Even that is something they argue over - who will give up their life for the other.
- Well-Intentioned Extremist: She has nothing but Earth's best interests at heart, but has virtually no qualms about using every available tool (both legal and illegal) in order to fulfill her objectives.
- Why Did It Have to Be Snakes?: She seriously hates flying — specifically space flight. It's mostly used for comic effect as it gives her reason to continue chewing out Cotyar and Bobbie, but eventually it reaches a non-comedic scene when while aboard the Razorback (a race ship), the heavy strain of continuous high G-forces coupled with her age constantly puts her at death's door from a brain aneurysm. It got bad enough that Bobbie had to slow down and risk getting blown up by Errinwright's ships just so she wouldn't keel over in the cockpit.
The UN Home Secretary, introduced in Season 4. She splits from Avasarala's government and makes her own run to become the next UN Secretary General, which she ultimately wins.
- Establishing Character Moment: Her first scene involves her arguing with Avasarala about the latter's reluctance to begin colonizing the ring worlds.
- Hoist by Her Own Petard: She spends much of her tenure as Secretary General sidelining her former boss Avasarala despite her experience and has her Reassigned to Antarctica. By the time Avasarala gets through to her that Marco Inaros is a real threat, it's already too late, and Gao ends up dying in the asteroid attacks he orchestrated.
- Nepotism: She's revealed to have leveraged personal connections to skip to the front of the line for vocational training. This is scandalous because countless others wait years or even decades for training.
- Rags to Riches: She grew up on Basic Assistance but used her intelligence to rocket through the ranks and become a respected politician.
- Reasonable Authority Figure: When the rocks start falling, shes the only one to listen to Chrisjen. Chrisjens allies also point out that, had their roles been reversed, Chrisjen also wouldnt have listened until it would be too late.
- Statuesque Stunner: Nancy's actress, Lily Gao, stands at 5'11 (180 cm).
- Puppet King: By his own admission, he has no idea what he's doing, so he just goes along with his cabinet. After this leads to Paster blowing up Pallas Station on advice from Delgado, thus guaranteeing that the Belt will be unified under Marco, the civilians in Paster's cabinet issue a vote of no confidence and replace him with the more thoughtful Avasarala.
- You Are in Command Now: He was originally the Minister of Transportation, but he becomes the new Secretary General by default after everyone before him in the line of succession is killed in the attacks. Obviously, he finds the task pretty daunting and immediately asks Avasarala to join his new cabinet.
Other United Nations Officials
The UN Undersecretary of Executive Administration. He's caught between continuing to assert Earth's dominance while reining in Avasarala's more aggressive tendencies.
- Acquired Situational Narcissism: Played for Drama when he betrays Avasarala. Errinwright was never the most modest person in the world, but after displaying a great deal of vulnerability in Season 2, his season-end success turns him into a smug manipulator who doesn't hesitate to take the most hawkish, violent route to end the Earth-Mars war.
- Adaptational Early Appearance: Like Avasarala, he doesn't appear until the second book, but in the series he's present from the beginning.
- Adaptational Expansion: He gets more characterization than in the books. In the series it briefly goes into his perspective and his personal life with his family.
- The Atoner: Subverted. After Avasarala discovers his involvement with Protogen, she rather graciously allows him to face the consequences on his own terms, with dignity and poise. The lives he's destroyed seem to weigh on his shoulders, and it even seems like he's contemplating suicide. He proceeds to outwit Avasarala and Jules-Pierre Mao, attempt to have Avasarala assassinated, murder Martian Defense Minister Korshunov and manipulate Sorrento-Gillis into an all-out war with Mars all to further his own agenda and avoid the legal consequences for his actions. He does all of this while (in his mind) maintaining the moral high ground and considering himself an unfairly maligned victim who just wanted to serve Earth.
- Big Bad Duumvirate: The partnership between Errinwright and Mao drives the entire plot of the series. Mao treats him more like The Dragon, however, which chafes Errinwright, and eventually Mao cuts him out completely following the Eros incident, subsequently partnering up with Martian delegation instead. Infuriated and backed into a corner, Errinwright manipulates his way out of that particular sticky situation by killing the Martian Defense Minister and trapping Mao into a deal he has no choice but to abide by, essentially putting Errinwright in complete control of their partnership.
- Corrupt Politician: Unbelievably so. The man orchestrated god-knows how many deaths (horrifyingly gruesome deaths at that) to advance the protomolecule project, and covered his tracks almost every step of the way with assassinations.
- Defiant to the End: When he's arrested, he doesn't try to weasel his way out like usual. He is utterly unrepentant, outright telling Sorrento-Gillis he has no regrets whatsoever.
- Disc-One Final Boss: Alongside Mao, Errinwright is the villain of the first two and a half seasons, and his prominence as a main cast member makes it easy to believe he's going to be the primary villain of the series. After his plans fail and he's exposed by Anna, he's arrested and not seen again. He's also the first one for Season 3 as he is arrested halfway through the season.
- The Dog Bites Back: An ungrateful and disdainful Jules-Pierre Mao treats him like a disposable pawn, in spite of the sacrifices Sadavir made for The Conspiracy. Sadavir ultimately turns the tables on him in a spectacular way, turning him into a pawn himself.
- Eerie Pale-Skinned Brunette: A Rare Male Example, but he fits. There is something eerie about how he looks and he is very corrupt.
- Even Evil Has Loved Ones: He might be responsible for thousands of deaths, but he cares deeply for his family and worries about what they'll think of him. He even claims that everything he did was for love, and shares a very touching moment with his son before putting his most ruthless plan into action.
- Heel Realization: In "Cascade", he finally gives up everything he knows about the protomolecule to Avasarala, apparently having been shocked into it by Eros and the Ganymede incident. He was already on the fence after the former, but the latter was the straw that broke the camel's back.
- It Gets Easier: By the start of Season 3, this is implied by his Ignored Epiphanies and Acquired Situational Narcissism.
- Jerk with a Heart of Jerk: While it first seems like he might've genuinely had a HeelFace Turn after the Eros Incident, it quickly becomes apparent that he has no real respect for human life and even goads the rest of the UNSC into sparking a possibly civilization-ending war with the MCR just to cover his own tracks and secure his own power base within the protomolecule conspiracy.
- Jerkass Has a Point: Errinwright might be a monster, but as he's arrested, he lets everyone know exactly what he thinks of Sorrento-Gillis...and he's laser-point accurate when he calls him a spineless, preening, easily-manipulated fool obsessed with his own ambition. Sorrento-Gillis proves him completely right seconds after, when he expresses gratitude to Anna for saving his reputation, which is surely at the bottom of anyone's list.
- Manipulative Bastard: It takes some serious skills to outfox Mars, Earth, Chrisjen Avasarala and Julies-Pierre Mao. After doing so, he gets the ear of Secretary General Sorrento-Gillis.
- Mole in Charge: He's a high-ranking government official with the president's ear, while also being part of the protomolecule conspiracy.
- Murder Is the Best Solution: Errinwright favors eliminating problems wholesale. He sends a black ops team after Holden and his crew, reasoning that, regardless of what involvement Holden may or may not have in the conspiracy, he's enough of a threat that just taking him out now is for the best. It's soon revealed he's a part of the conspiracy that's stirring up trouble, which means he was likely trying to silence them and saw it as a good opportunity. He also has Frank assassinated, kills Korshunov and advocates for the most violent solutions in the war with Mars.
- My God, What Have I Done?: Happens twice, both of which quickly become Ignored Epiphanies.
- He has a panic attack when his elaborate plan to murder a Mars diplomat succeeds, but then proceeds to use his initial freak out to cover his tracks.
- He's clearly horrified when his machinations result in a nuclear attack that kills two million people in South America, but instead of accepting his role in what happened, he blames the Secretary-General for waiting too long to enact his plan and uses the incident to push for an even more aggressive policy toward Martian "aggression".
- Never My Fault: Errinwright refuses to accept blame for his actions. He never admits full culpability; if he did something evil, it was for love and the greater good, or it was Mao's manipulations, or Sorrento-Gillis wasn't quick enough on the draw, or Anna was too much of an idealist. It can never be that Errinwright is just a manipulative snake who doesn't care who he hurts as long as he gets what he wants.
- Non-Action Big Bad: Errinwright is a politician and never meets any of the heroes except Chrisjen and Anna who are also both non-combatants. His threat is tied to his ruthlessness, political manipulation, and authority to command military and assassinations.
- Reasonable Authority Figure: He advocates a measured approach to diplomacy and attempts to find middle-of-the-road solutions to problems. That being said, he doesn't do much to stop Avasarala's brutal methods. This is reversed in Season 2, with Errinwright advocating a much more aggressive stance against Mars and betraying Chrisjen to hide his alliance with Mao.
- Redemption Rejection: Errinwright could have saved countless lives and prevented a war between Earth and Mars by owning up and accepting the consequences, but after realizing he isn't going to get off scott-free for his involvement in the Eros Incident, he quickly turns the other way and back stabs Avasarala in the hope of saving his own skin.
- Sharp-Dressed Man: As befitting a government official with outside interests, Sadavir is always impeccably turned-out.
- Treacherous Advisor: To Sorrento-Gillis. Errinwright is the one who pushed him to go to war, and continually manipulates him to take drastic action against Martian "aggression".
- Villainous Breakdown: He appears to have one in Season 2 once he surrenders his knowledge of the Protomolecule to Avasarala because of how he as a servant to Earth almost got it destroyed. He emotionally prepares himself and his family to suffer the consequences for his role as being Mao's partner. However, this is subverted as he regains his composure when he sees an ideal opportunity and puts his greatest play into action. Later, when he's arrested, it's Averted completely. See Defiant to the End
- Walking Spoiler: He comes off as a rather bland authority figure compared to Chrisjen in Season 1. He is, however, ''so'' much more.
- War Hawk: Errinwright pushes Earth and Mars into a war largely to save his own hide and partly because he truly views the MCR as a threat, and from there on, favors the most violent possible measures to make Earth victorious.
- Well-Intentioned Extremist: He claims that all the monstrous acts he committed were borne out of love. Specifically, he fears the MCR will destroy Earth if it gets its hands on the protomolecule, and resolves to destroy Mars before they get the chance.
- Worthy Opponent: Interestingly, he seems to regard Anna as this, despite otherwise not thinking much of her. When he's arrested, he ignores Sorrento-Gillis and (correctly) assumes Anna was the one to bring him down. He rants to her about his hatred for Sorrento-Gillis, seemingly because he knows she'll understand.
The Earth ambassador to Mara.
- Being Good Sucks: He genuinely cares about the Martians, which Avasalara exploits to learn if they were behind the destruction of the Canterbury, ruining his career in the process.
- Bus Crash: After being absent since "Remember the Cant", he's revealed to have been Killed Offscreen by a UN hit squad several episodes later.
- Happily Married: To Craig. Their marriage is implied to have still remained a loving one even after Frank's career was ruined.
- Never Suicide: His death is set up to look like a suicide. Though it was by all means plausible and highly likely, Avasalara isn't fooled for a second.
- Put on a Bus to Hell: He has his career ruined, and is forced out of Earth's government and banned from Mars, a Fate Worse than Death for him. Then he dies offscreen several episodes later, courtesy of Errinwright.
- "The Reason You Suck" Speech: He gives one to Avasalara on her ruthlessness and obsession with winning.
- Token Good Teammate: He's the most scrupulous and compassionate members of Earth's government, which results in him being blindsided by his more ambitious and ruthless colleagues.
- Too Good for This Sinful Earth: He's one of the few genuinely scrupulous and moral authority figures in the show, and is murdered on Errinwright's orders.
- Unwitting Pawn: Avasalara uses him as one to ferret out where the Martians are storing their stealth technologies, which leads to his life being ruined.
- We Hardly Knew Ye: He's only around for one episode before being Put on a Bus and Killed Offscreen.
An incredibly moral and anti-war United Nations Navy Admiral.
- Death by Adaptation: He's shot by Nguyen during his attempt to take the Agatha King back from Nguyen.
- A Father to His Men: Souther cares a great deal for the people under his command, and they love him in return.
- Souther also knows each of his commanders personally. He was the only member of the UNN high command who knew that a particular captain did not attend the fleet academy, making him the only admiral to see through Avasaralas white lie.
- Four-Star Badass: According to the Martians, Souther has left a trail of MCRN wreckage in Jupiter's orbit by the time UNN Agatha King reaches Io.
- General Failure: Errinwright insinuates that Souther is one of these during a stressful UN meeting, but he's just trying to justify shooting a Martian ship that could jeopardize his plans. In reality Souther is a very competent and thoughtful commander. Captain Kirino of MCRN Hammurabi even notes that hes damn good at knocking Martian ships out of the sky.
- Good Is Not Nice: He's blunt and stern, but unquestionably a good man.
- Honor Before Reason: He has a strong moral compass, but this sometimes causes problems for him. He could be the commanding admiral of the Earth fleet instead of Nguyen, had he not stepped down for moral objections. He even hesitates to mutiny against Nguyen, despite having widespread support.
- Jerk with a Heart of Gold: Souther isn't always an easy person to get along with; he doesn't mince his words and butts heads with Avasarala frequently. However, he's a deeply moral man who understands the human cost of war.
- Killed Mid-Sentence: As he's announcing the illegality of the Earth-Mars war to their respective fleets, Nguyen shoots him in the stomach, killing him.
- The Mutiny: He and his loyal crew rebel against Nguyen when it becomes clear the admiral won't listen to reason.
- Put on a Bus: He's absent for much of Season 2 after being reassigned to Jupiter Fleet, but returns in Season 3 when his flagship rescues Cotyar's stricken shuttle in the Belt.
- Race Lift: He is white in the books.
- Reasonable Authority Figure: He argues against escalating the situation with Mars and is one of Chrisjen's more trustworthy coworkers, even if they don't personally get along.
- "The Reason You Suck" Speech: He outright calls Avasarala quite possibly the worst person he's ever met — in the same room that sits the likes of Errinwright and Nguyen — for her manipulations.
- Resign in Protest: He steps down as UN Fleet Commander rather then go along with the senseless UN decisions that have a high chance of turning the Cold War with Mars into a shooting war. He's then transferred to command the UN's Jupiter Fleet.
- Surprisingly Sudden Death: Souther is very abruptly shot and killed by Nguyen in the midst of his mutiny. It's so shocking that Nguyen's people are able to get the upper hand on the other mutineers.
- Worthy Opponent: He may not like Avasarala, but he does appreciate where she comes from and respects her for that. That's why he refuses to believe she'd betray Earth in Season 3.
Fleet Admiral Augusto Nguyen
A war-mongering Earth admiral who rises in rank as tensions between Earth and Mars increase.
- Adaptational Villainy: While his novel counterpart was already pretty despicable — he was a War Hawk and a Dirty Coward who launched the protomolecule soldiers against Mars in an attempt to save his own skin, then tried to use humanity's safety as a bargaining chip for his life — this version is worse by an order of magnitude. It turns out he hates all non-Earth humans, considering them "insects", and was actively planning genocide against Mars from day one. He even murders his fellow UN admiral, Souther, for trying to obstruct his plans.
- Asskicking Equals Authority: Nguyen is no Armchair Military jerk; he's a very capable and physically threatening jerk. He manages to regain control of the Agatha King by swiftly turning the tables on the mutineers, killing or arresting all of them.
- Defiant to the End: As he awaits certain death aboard the Agatha King, he remains unrepentant, smugly insulting Alex for his heritage.Alex: Aww, bless your heart. Yknow, I may just have to shoot this asshole.
- The Dragon: He's Errinwright's chief enforcer in the UN Navy, and one character explicitly describes him as being "Errinwright's creature". And by proxy, this makes him part of the Protogen conspiracy.
- Establishing Character Moment: When Chrisjen is trying to figure out why a Martian ship would fire missiles near an Earth ship, Nguyen's first response is "Who cares?! Fire back!", thus letting the audience know that he is a bloodthirsty War Hawk.
- Evil Counterpart: To Admiral Souther. They've worked together a long time (Souther even calls Nguyen "Gus"), but while Souther is a largely even-tempered man who wishes to avoid an unnecessary war with Mars, Nguyen is a fanatical warmonger who conspires with Errinwright to destroy Mars.
- Fantastic Racism: In his final moments, he reveals himself to be a virulent racist who despises Martians with every fiber of his being, to the point he outright calls them inhuman and compares them to ants.
- Freudian Excuse: Discussed. He was one of the few survivors of a particularly brutal Earth/Mars battle and an officer suggests that Nguyen is constantly thinking over the crewmates he lost. While its truth is debatable, it certainly provides reasoning for his War Hawk tendencies.
- Final Solution: He tries to exterminate the population of Mars (which consists of over seven billion people) by blanketing the planet with protomolecule hybrids.
- General Ripper: The man despises Mars and will look for any opportunity to get into a war with them. Eventually, he gets his wish. As he awaits death aboard the crippled Agatha King, he goes into detail about his hatred for Martians, revealing that he's always been a genocidal madman.
- Hate Sink: Is an utterly loathsome excuse of a human being, with him quickly Jumping Off the Slippery Slope from being at first just a rude Jerkass to being a genocidal War Hawk that even kills his fellow soldiers when they refuse to carry out his despicable agenda. He's ultimately a perfect example of everything that's inherently wrong with Earth in The Expanse.
- Hypocrite: Often utilizes his rank in the chain of command to justify his brutal tactics during the UN-Martian War, but is perfectly willing to fight against the Anti-Mutiny staged against him once it becomes clear that he's part of the Protogen conspiracy and his actions are illegal.
- Hoist by His Own Petard: After he orders launching the hybrid pods at Mars, one pod is shot down and hit the Agatha King instead.
- Insane Admiral: An incident during the Vesta blockade in which he saw many of his men die horrifically at the hands of the MCRN has turned him into a War Hawk who wants to see Mars pay, regardless of the cost or what he has to do. This involves waging an illegal war and firing on his own men. His last act is to attempt genocide on Mars by firing the hybrid pods at the planet.
- Jerkass: Even putting aside his viciousness, Nguyen is just a downright unpleasant man who dismisses and scoffs at everyone who doesn't see eye to eye with him.
- Kick the Dog: After mortally wounding the Agatha King's captain during the mutiny, he shoots her in the back — twice! — as she tries to crawl to safety. He also destroys a UNN patrol skiff when its crew refuse to follow his illegal orders. None of those people posed any actual threat to Nguyen or his plans.
- War Hawk: Nguyen is very vocal about his desire to fight the MCR, in contrast to Souther's anti-war stance. He's been chomping at the bit for years.
Admiral Felix Delgado
A UN Admiral stationed on Luna.
- Deadpan Snarker: He has a dry wit to match Avasarala's vulgar one.
- General Ripper: Not even close to someone like Nguyen, but after the Inaros terrorist attacks he does advocate attacking in kind by targeting Belter civilians.
- Revenge Before Reason: Avasarala asks him to be on her cabinet, valuing his talent and brutal honesty. However, he refuses and instead opts to join a combat group (effectively a demotion) to hunt down Marco Inaros, despite the fact that he could do more for Earth as a cabinet member.
- Well-Intentioned Extremist: He is unconcerned about escalating the conflict with the Belt to protect Earth. Producer Ty Franck explains it as partly motivated by guilt for not doing as much as he could, but also because, as a military man, Delgado can only see the military options. Avasarala understands that Delgado is not coming from a place of bigotry or self-interest, and the two part on good terms.
Other U.N. Characters
A criminal hacker and corporate spy who stows away aboard the Rocinante. The crew let him live because he might be useful.
- All There in the Manual: His surname is never spoken in the series, instead being listed in official recaps and in the board game.
- Asshole Victim: For all his betrayals and machinations, his fate is a grisly one — mainly being devoured and assimilated by the Protomolecule. Yet also completely deserved.
- Badass Boast: Claims that he's a very good spy. And fair enough to him, he's genuinely competent and knows his shit, but not for one second does he ever win the Roci crew's trust.
- Bio-Augmentation: He has ocular and communications implants that he can control by blinking and tapping his fingers.
- Easily Forgiven: Averted. He runs into Holden while escaping Eros and begs to be allowed back onto the Rocinante. Holden toys with him for a minute, then leaves him behind.
- Electronic Eyes: One of his eyes is a cybernetic implant that can interface with other technology. Bonus points for being played by the voice actor of Adam Jensen, one of the characters whose eye is shown by the page image.
- Faux Affably Evil: Kenzo is transparently self-serving and loathsome, but he tries to act like an affable Punch-Clock Villain towards the crew.
- Gory Discretion Shot: [[spoiler:He's last seen
- Hate Sink: He's a self-serving, ungrateful, and manipulative prick who continuously tries to screw over Holden, the one man who went to bat for him.
- I Have a Family: Says this word for word. After what he put Holden through, he's not buying it and he's clearly bluffing.
- Jerkass: With a dose of Faux Affably Evil. He tries to come off as affable and reasonable, but he's an incredibly transparent dick. The crew puts up with him purely out of necessity.
- Karmic Death: After betraying the crew on Eros, he is left behind and consumed by the protomolecule. Since we don't know what the protomolecule is supposed to do, he might not be dead — but we've never yet seen anyone survive it.
- The Mole: Avasarala's, though originally he was a corporate spy digging up dirt on Fred Johnson at Tycho, until Chrisjen blackmailed his handler.
- Skewed Priorities: When Amos is going to throw him out the airlock, Kenzo's main concern outside of dying is that he really has to pee.
- Token Evil Teammate: Averted. Kenzo gets a fair degree of dialogue and development, and it looks like he'll become a regular, but after he calls down a tac team on the Blue Falcon and flees, it becomes pretty clear that's not happening.
- Ungrateful Bastard: Kenzo rewards Holden's decision to spare him by calling a tac team down on the crew the first chance he gets.
A security professional and former UNMC intelligence officer working for Avasarala.
- Ascended Extra: He's a very minor character in Caliban's War with only a couple of scenes, while he's introduced much earlier and has a much more prominent role in the series.
- The Atoner: The reason he works for Chrisjen and seems to genuinely care that she succeeds is because, in his own words, he got her son killed.
- Deadpan Snarker: He has a very sardonic sense of humor that he exhibits frequently.Chrisjen: You're losing a lot of blood!
Cotyar: (Beat) I'll try to bleed slower.
- The Dragon: To Chrisjen, though they are both on the side of good.
- Failure Knight: He states that he's the reason Chrisjen's son died. It's the reason he works for her despite not liking her much.
- Off Screen Moment Of Awesome: Manages to survive some kind of nasty encounter with a protomolecule infectee aboard the UNN Agatha King. Unfortunately, it smashed through the helmet visor of Cotyars emergency space suit, infecting him as well, leading to his Heroic Sacrifice.
- Shoot the Dog: Murders Theo so he won't break under UN interrogation and reveal Avasarala's survival to Errinwright and his allies. He regards it as an unfortunate necessity, and tells Theo how sorry he is as he breaks his neck.
- Taking You with Me: Trapped on the Agatha King and infected by the protomolecule, he rigs the reactor core to explode so the ship will be destroyed along with the protomolecule."Im disabling the magnetic containment on the main reactor. Detonation in... [sigh] How the fuck should I know? Im not an engineer!"
- Teeth-Clenched Teamwork: He loathes Chrisjen and will take any opportunity he can to make fun of her, but through her son he's honor-bound to her. He also really dislikes Draper, and doesn't take kindly to her tagging along thanks to her betraying her nation. That said, he still supports her and even brings her Powered Armor to Mao's yacht, knowing that shit would get rough and he'd need her.
- Troll: Gleefully fucks with the Martian delegation when Draper escapes from her quarters, sending in random policemen and traffic pulls their way for pointless inspections when they go looking for her. Mostly to buy time for Chrisjen to catch up and talk to her, but also because it's just funny.
- Snark-to-Snark Combat: 80% of his dialogue is him and Chrisjen trying to out-snark one another.
- The Spymaster: He's quite possibly the best spy in the system, and his intel network seems to be never ending. Precisely why Avasarala sought him out — she needs someone who sees everything on her side.
- Undying Loyalty: Not to Chrisjen, but rather her son. He promised him he'd look after her, and will do so no matter the cost.
A UNMC colonel and primary science officer assigned to the UNS Arboghast to investigate the Eros impact crater on Venus.
- Boring, but Practical: His job entails explaining science to people who only know war and politics. As a result, he tends to stay firmly planted in known and solid scientific reality instead of getting caught up in flights of fancy, the way more imaginative scientists like Michael Iturbi do. Michael thinks Janus suffers from a severe lack of imagination, but is still regardless a respectable scientist.
- Hidden Depths: Despite the nature of his work, he's still mesmerized by the wonders of science.Janus: When I was little, I was fascinated by stars. I thought they were magic. I kept coming up with all these crazy theories about how they worked. I drove my father crazy with all my questions.
Michael: Oh, I'm sure there were many other reasons.
Janus: I wanted to believe in magic.
Michael: Well, you know, that's normal for a child, right?
Janus: That's because children are stupid. When I grew up and learned the real explanation for the stars, they became even more amazing.
- Jerk with a Heart of Gold: He's a dick, but deep down he's a good man and reasonable officer. He's just a bit high-strung is all.
- The Stoic: He only has a single expression. One more reason why Michael loves to tease him.
- Teeth-Clenched Teamwork: He hates Michael Iturbi's guts due to his status as a pop-scientist and "radical dreamer" with wild theories, but eventually warms up to him during their mission.
- Uncertain Doom: It's not clear exactly what happened to him and the rest of the Arboghast's crew on Venus, but it's probably a safe bet he won't be coming back.
- Unfortunate Name: Michael claims that because he's Portugese, the "J" in his name is silent, which means it's technically pronounced...well, you know.
A UN scientist assigned to the UNS Arboghast.
- The Charmer: He's a very charming man, particularly with women (he implied to Janus, possibly as a part of his cover, to have slept his way on the expedition ship via Avasarala).
- Deadpan Snarker: Half of his dialogue is snark at Janus's expense.
- Fire-Forged Friends: He and Janus do not get along at first, but eventually the two start to see eye-to-eye.
- A Good Way to Die: When the Arboghast gets disassembled in Venus's upper atmosphere by the protomolecule, the rest of the crews' reactions are either Oh, Crap! or "What the hell is going on?" The look on Iturbi's face is more like "This is a cool way to die!"
- Likes Older Women: He started to flirt with Avasarala at their secret meeting despite her being old enough to be his mother, possibly only in jest.
- The Mole: Avasarala's, aboard the Arboghast with intent to send her all information without Janus or Errinwright filtering it.
- Properly Paranoid: Firmly believes that Eros was the result of aliens, or alien technology. He's absolutely right.
- The Smart Guy: He's as accomplished a scientist as Janus, but he's more radical and creative whereas Janus is more practical and hard fact-oriented.
- Uncertain Doom: It's not clear exactly what happened to him and the rest of the Arboghast's crew on Venus, but it's probably a safe bet he won't be coming back.
Chrisjen's husband. An academic.
- Bus Crash: He was apparently killed in the asteroid attack on Earth by the Free Navy, and a big part of Chrisjen's story arc in season five is her eventually having to accept that.
- The Consigliere: While not often, he does offer support and advise when Chrisjen needs it.
- House Husband: Discussed. He remarks that First Husbands are expected to give up their jobs but quips that he's keeping his because he has tenure.
- Morality Pet: Is Chrisjen's. In the end, he's one of the few things that keep her from going truly deep.
- Nice Guy: A sweet old man who dotes on his entire family and is wracked with worry over his wife.
- Pet the Dog: Was the only person to talk to Bobbie while she was being ignored by her fellow Martians, and he was even kind enough to sit next to her instead of his wife.
- Put on a Bus: At the end of season 1, Chrisjen sends him to Luna to keep him out of danger. The Bus Came Back in season 4, once Chrisjen is no longer in immediate danger, and helps her with her election campaign. When the campaign fails, he returns to Luna of his own volition out of disgust for her election tactics. When Chrisjen is posted on Luna herself in Season 5, Arjun returns to Earth in turn, which gets him killed in Inaros' triple Colony Drop.
- Satellite Character: Since he isn't a political force like the most of the other Earth characters, he's largely just Chrisjen's supportive husband.
- The Other Darrin: Is played by Brian George in the first two seasons, but is played by Michael Benyaer in season four dur to George being unavailable.
Rev. Dr. Annushka "Anna" Volovodov
A European Methodist pastor and an old acquaintance of United Nations Secretary-General Esteban Sorrento-Gillis.
- Adaptation Dye-Job: She's a redhead in the books.
- Belief Makes You Stupid: Averted.
- Beware the Nice Ones: Just because she's incredibly nice doesn't mean that she won't tase you to stop you from horribly killing someone else.
- Big Damn Heroes: Saves Naomi's life by knocking Clarissa Mao/Melba out with a taser.
- The Conscience: Anna is very much the angel on Gillis' shoulder, in opposition to the devil that is Errinwright. In their first real scene together, they're on opposite sides of the table. Anna is dressed in white, while a slouching Errinwright is dressed in his usual black.
- In Season 3, she tries imparting some moral wisdom to Amos.
- Establishing Character Moment: She is introduced being escorted by police while protesters are held back by riot police right in front of her. When one of the protesters falls over a barricade and gets a nasty-looking gash on his forehead, she tasks the nearest riot police with getting him to first aid station. This all establishes her as moral, principled, willful and practical.
- Hair of Gold, Heart of Gold: She's a blonde and a very bright presence, driven and moral without being naive.
- Happily Married: Has a very positive relationship with both her wife and their daughter, though its recently been under some stress due to her constantly traveling for her work throughout the system.
- Heroic BSoD:
- She becomes a sobbing mess after Sorrento-Gillis and Errinwright edit the speech she wrote to call for the annexation of Mars and resolves to just go back home to her wife and daughter because she thinks that she's a complete and utter political failure. She snaps out of it when Avasarala sends her evidence that Errinwright is conspiring with Protogen.
- Anna suffers another BSOD on the trip to the Ring. She's so caught up in the politics and historicity of the moment that she brushes off a crewman asking her for counsel, missing the suicidal signals he's giving off. When he does kill himself shortly afterward, Anna has to conduct his memorial service. The experience forces her to reevaluate her priorities, and it's probably still looming in her thoughts when she commits to stopping and then trying to rehabilitate Clarissa.
- Honest Advisor: Sorrento-Gillis hires her explicitly because she's a strong-willed idealist who'll tell him the hard, ugly truth right to his face and won't try to flatter or manipulate him. Unfortunately, Sorrento-Gillis is so weak-willed that he almost immediately forgets why he wanted her around in the first place.
- Good Is Not Soft: She might be a very kind and sweet pastor, but quickly develops Nerves of Steel and even helps force Clarissa Mao's HeelFace Turn via a very candid "The Reason You Suck" Speech.
- I Just Want to Be Special: Despite her sophisticated and kind demeanor, Anna very much craves excitement and danger and desperately wants to be a part of something special. Despite knowing how her wife would feel, she elects to stay behind on the Thomas Prince to see what lies beyond the Ring. This craving also led her to innocently ignore a desperate soldier and fellow parishioner who eventually killed himself to her horror. Later on, she recklessly follows Clarissa in the vacuum of the Slow Zone to the Rocinante to stop her from trying to kill Holden.
- Lipstick Lesbian: She's a very attractive and traditionally feminine woman who also happens to be married to another woman.
- Morality Pet: Amos all but declares her to be this for him in "Congregation."
- Nerves of Steel: Starts to develop these after her initial Heroic BSoD.
- Nice Girl: She's a genuinely sweet and kind person who only aspires to prevent war and help explore the universe (as seen during her story arc in the latter half of Season 3). In fact, her gentle (yet harsh) advice is one of the main reasons why Clarissa Mao would eventually undergo a HeelFace Turn.
- Odd Friendship: With Amos Burton.
- Salt and Pepper: Her wife is black.
- Spanner in the Works: For The Conspiracy during the first half of Season 3.
- We Used to Be Friends: Although she agrees to work with Sorrento-Gillis, she hasn't forgiven him for some as-yet-unknown incident between them that led to a falling out. Years later, she's surprised to find she's still angry about it. It's later revealed that Sorrento-Gillis knowingly sent protesters into a military base for the purpose of becoming martyrs. No wonder she's pissed.
- What the Hell, Hero?: She is pissed when Sorrento-Gillis twists her speech into a rallying cry to decisively win the war with Mars, telling him off before storming out without even giving him a chance at a rebuttal.Anna: What the hell was that?!
Anna: No, you twisted my words. You made me part of everything that I hate — about all of this!
Sorrento-Gillis: Now, that's not fair.
Anna: I can't believe I fell for this again! I am such an idiot. You snapped your fingers, and I am right back to following you around, mopping up the blood.
Errinwright: What the world needs right now is precisely—
Anna: [to Errinwright] You don't get to speak to me! Not ever again. [to Sorrento-Gillis] And you didn't need to be his hand puppet. You could've been better than this. You should have been more than this. I used to believe that there was a decent man somewhere inside you buried under all that ambition. I'm sorry I was so wrong.
- Worthy Opponent: Errinwright considers her to be this for him after she successfully brings his involvement in The Conspiracy to light.
A reporter who films a documentary about the Rocinante's crew.
- Actor Allusion: This wouldn't be the first time Anna Hopkins has played a filmmaker in a futuristic setting.
- Adaptation Expansion: Her last appearance in the books is when Holden rescues her from the Free Navy. In the series, Monica temporarily joins the Rocinante's crew so she can learn just what the Free Navy is up to.
- Almost Out of Oxygen: Her efforts to escape from a prison cell that turned out to be a cargo container in Tycho Station's container port result in its slow but unstoppable depressurization. She actually was completely out of oxygen by the time the heroes find her, but advanced medical technology succeeds in saving her life.
- Distressed Damsel: She's captured by the Free Navy when she tries to send Holden information on a mysterious faction trying to research the protomolecule. Holden manages to rescue her. She actually would've successfully freed herself if not for the unfortunate fact that her prison was surrounded by hard vacuum, which she had no way of knowing. When the Free Navy tries to kidnap her again, she's ready and is able to protect herself with Holden's help.
- Electronic Eyes: She upgraded herself with a cybernetic eye between Seasons 3 and 5. Its ability to record and transmit everything she observes ends up saving a lot of lives, including her own, on multiple occasions. Visually it's only recognizably artificial when it's convenient to the plot; most of the time it looks completely normal.
- Face Death with Dignity: In Season 5, when Holden takes the Roci on an almost guaranteed suicide run while she's aboard, Monica clearly isn't happy but takes the news calmly and without any protest. They all make it out without a single scratch.
- Guile Hero: She's very much a Non-Action Girl, but her wits and resourcefulness have gotten her out of serious trouble a bunch of times. Her journalistic instincts also let her spot crucial details that no other character picked up on.
- I Have Boobs, You Must Obey!: Subverted. She tries to use her sex appeal to get some juicy info out of Amos, but he shoots her down for various reasons, in no uncertain terms.
- Intrepid Reporter: Is determined to get to the bottom of the various mysteries surrounding the Roci's crew. In the fifth season, this leads to her risking her life by joining the Rocinante's pursuit of the Zmeya and even working as a crewmember of the ship during her stay.
- Jerk with a Heart of Gold: She invades the Rocinante crew's privacy in the name of journalism while reminding them that her organization is paying for their legal fees. However after the Ring incident begins she earnestly disseminates much-needed information to the survivors and gets Anna's message out to the rest of the fleet.
- Ms. Fanservice: She's an attractive woman who spends most of her scenes in skintight clothing.
- She Knows Too Much: The Free Navy attempts to abduct her after her investigations reveal that they are involved in new protomolecule experiments.
- Thrown Out the Airlock: Non-fatally by Amos, along with Cohen. It's actually an attempt to contact the MCRN cruiser in pursuit of the Rocinante after their comms were sabotaged.
Elio "Cohen" Casti
Monica's cameraman, helping her film aboard the Rocinante.
- Bio-Augmentation: He has extensive wiring visibly implanted just beneath his skin which allows him to remotely control drone cameras and "sense" technology. He is also blind, but eye augmentations allow him to "see" through his drone cameras.
- Half the Man He Used to Be: He was cut in half by a door when all the ships were stopped.
- Killed Offscreen: He dies between Amos tossing him out an airlock and Monica's next appearance.
- The Mole: He's working for Melba, although he's just a paid stooge and knows nothing of her actual plans or motives.
- Straight Gay: He comes on pretty strong to Amos a few times, who rejects him.
- Thrown Out the Airlock: Non-fatally by Amos, along with Monica. It's actually an attempt to contact the MCRN cruiser in pursuit of the Rocinante after their comms were sabotaged.
- Unwitting Instigator of Doom: He is tricked into sabotaging the Roci under the guise of stealing records, unaware of the true nature of his sabotage until it's too late.
A wealthy woman who gained pasage on the Thomas Prince because she thought it would be interesting.
- Age Lift: Her book counterpart was already an adult when Julie and Clarissa Mao were children; Clarissa knew her as "Aunt Tilly" and she mentions to Anna Volovodov that she "dandled both those girls on my knee back in the day". In the show, they all appear to be about the same age (Genelle Williams is actually younger than either Florence Faivre or Nadine Nicole).
- Almost Dead Guy: She survives being impaled just long enough to tell Anna about Clarissa Mao.
- Ambiguously Bi: She is married to one of the richest men in the solar system, and she is very happy to flirt with the very gay (and very married) Anna.
- "Blackmail" Is Such an Ugly Word: Inverted. She manages to pull a few strings in order to remain aboard the Thomas Prince, and describes it as extortion but she prefers to use the word blackmail instead.
- Impaled with Extreme Prejudice: She is fatally impaled on a piece of debris from a combination of Clarissa trying to kill her for knowing her true identity and the Thomas Prince's suddden deceleration.
- Odd Friendship: Flighty, snarky, rich, non-religious Tilly becomes rather good friends with idealistic pastor Anna. Tilly even flirts with her.
- Rich Boredom: She describes herself as an "aging debutante," and the reason she is aboard the Thomas Prince is because she is bored and being close to the Ring is a chance at thrill-seeking.
A popular Christian preacher who is part of the Thomas Prince's religious delegation.
- Demoted to Extra: In the books, he's a minor antagonist. This version of Cortez is just a Foil to Anna who exits the plot after a handful of scenes.
- Foil: To Anna, whose curiousity and courage contrasts with Cortez's caution.
- Put on a Bus: Departs the Thomas Prince before she enters the Ring.
- Screw This, I'm Outta Here!: When the civilian contingent is evacuated, he's all too happy to leave, rejecting Anna's proposal to stay aboard. As he sees it, whatever machinations led to the Ring don't involve God, and that concerns him greatly.
The ruler of the Baltimore underworld and a childhood friend of Amos.
- Affably Evil: He's a crimelord, but he has the cheerful mannerisms of a Silicon Valley startup CEO.
- The Don: He's the head of a criminal organization that rules Baltimore from the shadows.
- Hidden Depths: This crimelord is also a master hacker, capable of giving people new identities.
- Pet the Dog: He's worried that Amos has come back to target him, but when he hears that Amos just want his late mother's husband to keep the house until he dies, Erich grants his request immediately.
- Put on a Bus: In "Nemesis Games", he parts ways with Amos for good to rebuild his organization on one of the ring worlds.
- Red Right Hand: His left arm is either deformed or his hand was removed at some point.
- Sunk Cost Fallacy: Erich is reluctant to help Amos and Clarissa steal a spaceship as he doesn't want to discard all the work he put into controlling the Baltimore underworld to waste. Clarissa convinces him that the Baltimore he knew died when the rocks fell and that he's just being stubborn.
- We Used to Be Friends: He and Amos were close as children, but as adults, Erich distrusts Amos out of the mistaken belief that Amos has returned to Earth to usurp him. Working together to escape Earth eases the tension between them and they part as friends in "Nemesis Game", with Erich going so far as to offer Amos a place in his new organization.
- Beware the Nice Ones: He's a friendly, easygoing man, but he's utterly pissed at Avasalara for ruining Frank's life and is nothing but cold and hostile to her.
- Happily Married: To Frank. Even after Frank's career was ruined, they still loved each other deeply.
- Nice Guy: He's friendly and lively. Even when angry at Avasarala for ruining Frank's life, he still allows her to go in his study to say goodbye.
- OOC Is Serious Business: His sullen, cold demeanor to Avasarala contrasts his generally friendly personality, showing just how angry he is.