Cassandra's younger sister and Wills friend. She was always overshadowed by her older sister, and wants a chance to prove herself.
- Anti-Hero: Even though she is trying to make the world a better place, she is forced to be the ruler due to Cassandra's death and makes some questionable decisions.
- Bunker Woman: Becomes this at the hands of Campbell in the season finale.
- The Chains of Commanding: Is faced with many difficult decisions over the course of the season.
- Didn't Think This Through: One of her critical character flaws is her lack of foresight, often not considering all the potential consequences of her choices.
- Nice Job Breaking It, Hero!: Her dismissal of the Guard's poor treatment of Lexie leads to her retaliation and the events of the finale.
- Reluctant Ruler: She's pushed into taking over after Cassandra is killed, and doesn't much like the position because it puts everything on her shoulders.
- Wrong Genre Savvy: In the first episode. She states explicitly that it's important to know your role in the story, and she's not the protagonist of this one because Cassandra is. She's wrong about both of them.
Allie's sister and the class president. A bossy girl, but the only one with a good head on her shoulders when things go haywire.
- Decoy Protagonist: She's introduced as the main character, with Allie being her Deuteragonist and Gordie being her Love Interest, but she's killed in episode 3.
- Ill Girl: Has a heart condition and a pacemaker.
- Student Council President: Before the students were exiled. This leaves her as the only one with any sort of authority, putting her into the role of the students leader.
One of Allie's closest friends, a foster child who lived in poverty outside city limits.
A friend of Allie and Will, and girlfriend to Harry. Takes on many responsibilities in the town early on, in contrast to her boyfriend.
- The Medic: Becomes this alongside Gordie when the two start running the hospital.
- Romantic False Lead: She breaks off her relationship with Will after realizing he has feelings for Allie.
- Took a Level in Kindness: Its implied that she wasnt particularly nice in high school, but after breaking up with Harry and siding with Allie, proves herself to be very sweet, supporting Becca in her pregnancy and teaching herself alongside Gordie how to be a doctor.
A once-popular student at West Ham with a reputation for parties. He does not cope well with the transition to the new society.
- Be Careful What You Wish For: He wishes that somebody would shut Cassandra up, and she gets murdered. He tries to get power over the town, and does so with the help of Campbell, becoming his puppet.
- The Friend Nobody Likes: During high school he was the most popular kid because of his rich parents and him throwing huge parties at his home. However, once all of that went away, many of the students in town want nothing to do with him, even the ones he thought were his friends, because they now see how selfish he is. There are scenes where teens won't even bother with him, unless he promises them something, like letting them borrow one of his fancy cars. This on top of having to share his assets with other teens has led him into a deep depression, which Campbell later uses to manipulate him into helping him take over the town at the end of Season 1.
- Humiliation Conga: In the normal world, Harry was rich, popular, and had a beautiful girlfriend. He loses all of these things in the first few episodes. He also develops a crippling drug addiction and severe depression. All of this leaves him very vulnerable to Campbells manipulations.
- It's All About Me: Harry is almost virtually incapable of putting the needs of others before his petty desires to the point that being forced to do so causes a Despair Event Horizon rather than Character Development.
- Jumping Off the Slippery Slope: Harry starts off as a jerk, but the events of episode three, in which he is forced to conform to the new society and share what he has, aside from losing his girlfriend, causes him to slowly start to lose it as he starts to want revenge on Cassandra for creating this new society.
- My God, What Have I Done?: Has this reaction when he realizes that him complaining about Cassandra and wishing she was dead inspired Dewey to actually kill her.
A bookish and intelligent student, Gordie investigates the towns disappearance and researches medicine.
- Informed Judaism: He mentions having a Bar Mitzvah and inviting Cassandra when they were young, but that's all we hear about his religion.
- The Medic: Becomes this alongside Kelly when they start running the hospital.
- Platonic Life-Partners: Is very close with Bean, but theyre just friends. Bean even gives him advice on his date with Cassandra.
- The Smart Guy: Shares this distinction with Bean.
One of the two Eliot brothers, Campbell has a manipulative and violent disposition. Most of the town finds him intimidating.
- Ax-Crazy: It's implied throughout Season 1 that Campbell is a textbook psychopath and he does nothing to make people think any different (in fact, he is often Brutally Honest about his nature), and even recognizes that most people are afraid of him.
- Cain and Abel: The Cain to Sams Abel.
- Dragon-in-Chief: Campbell is clearly more competent than Harry, the Guard, and even Lexie who he convinces to take control but theyre all clearly his puppets who he only needs because no one will support him alone due to his 0% Approval Rating with the masses.
- Faux Affably Evil: Presents himself as laid back, honest, and cooperative. Most people dont buy it, nor should they.
- Hate Sink: Campbell clearly establishes himself as this early on when he takes advantage of his newfound freedom by banning his own brother Sam from their house (calling him a little fag in the process) and only gets worse as the story goes on by emotionally and physically abusing Elle while alienating her from the rest of the people in town. His own cousins and brother hate him. The only people who tolerate him are Elle (increasingly out of fear) and Harry (because Campbell supplies him with drugs).
- Man Behind the Man: Campbell makes himself this, after he successfully overthrows Allie's rule and puts Harry and Lexie out in front as his puppets to lead the townspeople.
- Manipulative Bastard: Very good at emotionally manipulating people. Sam warns Allie that hes still dangerous even when chained up because his biggest weapon is his words.
- Sibling Yin-Yang: With Sam. Campbell is controlling, harsh, and manipulative.
- The Sociopath: Diagnosed as one, in fact. Sam tells a story about how he cut of the wings of the family's pet bird just to watch it struggle as it died.
- 0% Approval Rating: Almost everyone finds him frightening and unlikable. The only people who really tolerate him are his girlfriend Elle and client Harry.
Somewhat arrogant and stand-offish, Elle is unpopular with many of the other female students. However, she catches the eye of Campbell.
- Alone with the Psycho: The whole relationship between Elle and Campbell is this. Campbell both physically and mentally abuses her and keeps her for having any kind of social life outside of being with him, not even with pets. It's clear she doesn't love him or want to be with him, but is afraid of what he might do if she tries to leave him.
- Break the Cutie: Her entire relationship with Campbell results in this.
- Bungled Suicide: After she fails to stop the guests at the Thanksgiving feast from partaking in the poison pie meant for Campbell, she quickly devours the rest of the pie with her fingers, both out of guilt and as an attempt to stop anyone else from partaking. She becomes very sick, but Kelly and Gordie are able to save her, much to her dismay.
The younger brother of Campbell. Deaf since his early childhood, Sam is almost a complete inverse of his sibling, being calm, friendly, and unambitious.
- Cain and Abel: The Abel to Campbells Cain.
- Deadpan Snarker: Has shades of this, which often ends with Becca telling him Dude, Not Funny!.
- Disabled Character, Disabled Actor: Sean Berdy is actually deaf.
- The Not-Love Interest: Plays this role to Becca, supporting her and acting as the father of her child, but they're Platonic Life-Partners.
- Platonic Life-Partners: With Becca.
- Sibling Yin-Yang: With Campbell. Sam is friendly, compassionate, and soft.
- Twofer Token Minority: Sam is a deaf teen, and he is also the only openly gay guy in the town.
Sam's best friend since childhood. Fluent in sign language, she often acts as his interpreter.
- The Beard: A particularly unique inversion in which Sam pretends hes not gay and says hes the father of Beccas baby because Becca doesn't want to admit she was knocked up in a random one-night stand. This causes some confusion among the town since Sam was openly gay beforehand.
- Camera Fiend: When the kids have a massive party their first night alone in the town, she stays on the side and records it. She's later seen taking pictures of events in the town so that the kids' history is recorded.
- One Drink Will Kill the Baby: Gets angry at Sam for giving her rum and coke because of this.
- One Night Stand Pregnancy: Something she's ashamed about, which leads to her and Sam pretending it's his.
- Platonic Life-Partners: With Sam.
- Shrinking Violet: She usually stays on the sidelines and tries not to get involved with stuff like prom and big parties. It's reinforced since the seemingly only time she went out to cut loose resulted in her pregnancy via a one-night stand.
- Teen Pregnancy: She got pregnant shortly before everyone was taken to New Ham.
A religious girl from the town and a friend of the Pressman family. She tries to keep religion going as a form of give everyone hope.
- Beta Couple: With Luke.
- Brainy Brunette: She's not one of the town's science experts, but she's very clever and logical when it comes to issues the town faces.
- Beware the Nice Ones: A milder version, but it still applies. Helena's very calm, composed, sweet and mild-mannered. But she knows how to shoot a gun and even stood up to Campbell when he came to her house looking for Elle, where she tells Campbell to 'Fuck off' and that he's 'not welcome here [at her home]'. And she wasn't there when Sam told Allie and the rest of her friends what Campbell's capable of, so it goes to show just how brave she is as well.
- The Heart: Shes considered the moral center of the town, and tends to be a voice of compassion and mercy. It's for this reason that Allie calls on her to act as Dewey's lawyer and later moderate the mayoral debate.
- Let's Wait a While: Insists in not having sexual intercourse with Luke because she's saving herself for marriage. Downplayed in that she's fine with them giving each other oral sex, and they end up only waiting until their engagement.
- Nice Girl: While occasionally haughty and direct, she is compassionate towards almost everybody.
- Only Sane Man: She is quick to point out various problems with the plans of others, such that attempting to confiscate all the guns would be pointless because anyone who wanted to hide one would be able to do so with ease.
- Slut-Shaming: Once mocked Elle as a "thot". She regrets this and later apologizes to her.
- Technical Virgin: At first, she wont have penetrative sex with Luke, but she does go down on him. Luke points out how silly this is, but she stands her ground. They finally do have intercourse once theyre engaged.
- Token Religious Teammate: She's the most religious member of the group, and makes an effort to keep the church going.
The former quarterback of the schools football team and boyfriend to Helena, Luke is highly popular and well-liked. One of the founding members of the Guard, he strives to keep peace in the town.
- Beta Couple: With Helena.
- Book Dumb: Is not well-read, but he has more emotional intelligence and better instincts than many people in the town.
- Lovable Jock: Hes a good-hearted, friendly guy who wants to do whats best for everyone.
- The Quarterback: Subverted—while this was his position, he rarely called the plays. It mirrors how he's the face of the Guard in New Ham, but ends up having to follow Jason and Clark's lead because he can't take charge.
- Token Good Teammate: Alongside Grizz, he's the nicest guy on the football team and later the Guard. This changes when he helps the Guard, Campbell, and Harry stage a coup.
A former member of the West Ham football team, Grizz is a member of "The Guard", an organization formed by several school athletes to keep order in the town. Despite the reputation of the athletes, Grizz is quite intelligent and cultured.
- Academic Athlete: Was on the football team but is also very into literature.
- Establishing Character Moment: He's introduced in the middle of a tense argument between Cassandra and Harry, where he compliments Cassandra (who is widely disliked by the people he hangs out with) on her performance in the school play. This sets him up as the Nice Guy who gets along with everyone.
- The next day, he also translates the graffiti on the church and recognizes it as a quote from the Bible, indicating his intelligence.
- Gentle Giant: He's very tall, and very caring about the people around him.
- Lovable Jock: Kind, caring, and knowledgable about many topics, it's no wonder so many people gravitate towards him.
- Nice Guy: He rarely insults people, instead giving them reassurance in the form of compliments and quotes from his favourite works.
- Only Sane Man: Is one of the few voices of reason in town.
- Straight Gay: Gwen is surprised to find out he's gay and when Grizz admits he didn't approach Sam in high school because he was pretending to be straight, Sam tells him he was very convincing.
An unfriendly girl, who dislikes the way things are being run in the town.
- Be Careful What You Wish For: Lexie believes Allie leads the town like a dictatorship and runs to beat her in an election for Mayor. She gets most of the people's support and seems like she will win, only to experience what a true coup and dictatorship looks like when Campbell takes over the town by force when he gets the Guard on his side, and makes himself the undisputed ruler with her and Harry as his puppet front men.
- Evil Is Petty: It's apparent that she'd drive the society into the ground just to spite Allie.
- Jerkass: She hijacks the improv skit at Thanksgiving dinner to mock Allie.
- Jerkass Has a Point: Her criticisms of the Guard are valid, considering they abused people within their custody several times with no consequence.
Another ex-Football player and member of the Guard, Clark is more arrogant and violent than his compatriots.
- Dumb Muscle: Almost worse than Jason. He's often drunk and comes up with terrible ideas.
- Power Corrupts: He first shows this when he beats up Dewey while they're in custody, hoping to get a confession but mainly just because he can. When he and Jason realize that the guard has been doing all of Allie's dirty work, they try to seize power for themselves and ignore anyone pointing out that it's a bad idea for what counts for the military to take over the government.
Clarks girlfriend and a friend of Kellys. Gwen is not a very friendly person, though she has her softer moments.
- Incompatible Orientation: Comes onto Grizz, who's gay and admits as much.
- Jerkass with a Heart of Gold: While she has her Jerkass moments (such as refusing to let Elle hang out with her friends, talking suggestively about her friend Kelly's boyfriend and dismissing Cassandra's concerns about the boys' violent behaviour as bitterness that no-one wanted to date her in high school), she's still shown to be a good person despite this.
- Your Cheating Heart: Was cheating on Clark with a man she met on a college tour, before the show started.
Another former member of the West Ham football team and member of the Guard.
- The Ditz: While not totally clueless, hes probably the dumbest member of the main cast. For example, his entirely serious suggestion on how to hold Dewey is to lock him in a car and crack the window.
- Dumb Muscle: He rarely thinks anything through, and even though he complains about always having to follow orders he usually ends up doing so repeatedly.
- Power Corrupts: When he and Clark realize that the guard has been doing all of Allie's dirty work, they try to seize power for themselves and ignore anyone pointing out that it's a bad idea for what counts for the military to take over the government.
An intelligent and upbeat student at West Ham High. She focuses on researching the town's disappearance, but also provides advice to Allie and Gordie.
- Asian and Nerdy: West Asian rather than East Asian, but otherwise plays this straight. She's the main science person alongside Gordie.
- Platonic Life-Partners: Is very chummy with Gordie, but they show no romantic interest in one another.
- The Smart Guy: Shares this role with her friend, Gordie.
- Token Religious Teammate: Is Muslim. She wears a hijab, and can be seen praying from time to time. However, her religious beliefs are out of focus compared to Helenas.
An unassuming and somewhat meek kid, Greg is considered beneath notice by most of the community. He tries to fit in with Harry and his friends, with limited success.
- Beware The Quiet One: He appears to just be a nobody, a quiet dork in a town full of big personalities. Hes Cassandras murderer.
- Loners Are Freaks: Several people note him to just seem a little weird. Hes more than a little weird, hes a murderer. Subverted, as hes not a complete loner, just a bit detached, and there are other withdrawn characters in the series who are more well-adjusted.