A 24-year-old woman who escapes her mundane hometown and a dull utility company job to work in Customer Experience at The Circle. She is initially eager to please and highly competent at her job, deeply impressed by the company's utopian campus. Driven by a desire for financial independence and a need to help her father, she quickly assimilates into the company's culture.

Mae's former college roommate and a high-ranking executive at The Circle. She is a cheerful, sarcastic leader holding a prestigious position that grants her significant access and influence. She acts as a confident mentor in the company's fast-paced environment, securing Mae a job and health benefits.

Mae's ex-boyfriend who remains in their hometown of Longfield, crafting chandeliers out of antlers. He refuses to engage with social media and serves as a vocal critic of The Circle's expanding influence. He maintains a warm, helpful relationship with Mae's parents, often assisting them with household emergencies.

Ty Gospodinov is the young, visionary founder of The Circle who invented TruYou, the platform that consolidates users' online identities. Meanwhile, Kalden is a mysterious, gray-haired man who roams the campus and takes a romantic interest in Mae. He operates outside the normal rules of the company, popping up unexpectedly to warn Mae about The Circle's ambitions.

One of the Three Wise Men who lead The Circle. He is the approachable, public-facing leader who champions transparency and global connectivity. He possesses a laid-back, friendly personality that makes him deeply beloved by Circlers, though he uses his charm to push employees into accepting radical surveillance initiatives gently.

The third member of The Circle's Three Wise Men. He functions as the company's cutthroat capitalist, driving its aggressive expansion and financial strategies. He has a stern, ruthless demeanor and enjoys displays of dominance, symbolized by his interest in aggressive deep-sea creatures.

A married couple living in Longfield who previously ran a parking lot. They are incredibly proud of Mae's new job and rely heavily on her for support as Mae's father battles the worsening symptoms of multiple sclerosis. They struggle with insurance companies until Mae secures them coverage through her employment.

A Circler working on a controversial project called TruYouth, which aims to plant tracking chips in children's bones to prevent abductions. He grew up in the foster care system after a severe family tragedy, fueling his obsession with security and facial recognition technology. He pursues Mae romantically but often acts without considering her boundaries.

An employee at The Circle who helps orient Mae. She shows off the company's culture of deep online research; she knows about Mae's fondness for Calder mobiles before they even speak.

Dan is Mae's team leader in Customer Experience. He emphasizes the importance of community and actively monitors Mae's participation in campus social events. He frequently calls her into his office to discuss her social media metrics, pushing her to prioritize her online presence over her real-world obligations.

A Customer Experience trainer who teaches Mae how to interact with clients. He stresses the need to inject humanity into customer service and monitors Mae's initial progress.

Josiah is an employee in human resources who helps guide Mae around the campus. He conducts a check-in regarding her lack of social participation, using the company's internal tools to track her hobbies. He pressures her to share her kayaking experiences online, viewing privacy as a form of selfishness.

Denise is an HR employee who works closely with Josiah to monitor employee engagement. She confronts Mae about her weekend absences, labeling her an 'enigma' for spending time off-campus. She aggressively pressures Mae to join an on-campus support group for multiple sclerosis rather than physically visiting her sick father.

The Circler responsible for activating Mae's internal and external social media profiles. She takes offense when Mae refers to these duties as extracurriculars, enforcing the idea that online participation is mandatory.

A Circler who becomes deeply offended when Mae fails to RSVP to his Portugal-themed brunch. He uses data scanned from Mae's laptop to invite her and expects constant social reciprocation.

Francis's friend who develops a dating app called LuvLuv. He uses Mae's online data without her consent during a live presentation to demonstrate how his app can plan the perfect date, prioritizing data over humanity.

A glamorous doctor at The Circle's medical clinic. She outfits Mae with a health-tracking bracelet and tricks her into swallowing a sensor, seamlessly integrating Mae's physical body into the company's data cloud.

The owner of Maiden's Voyages, a kayak rental facility. She knows Mae as a regular customer and eventually helps clear her of theft charges after Mae borrows a kayak after hours.

An outsider politician who publicly declares that The Circle is a monopoly that needs to be broken up. She soon faces backlash and scandalous revelations that threaten her career.

A politician who agrees to become the first elected official to go fully transparent, wearing a camera at all times to prove she has nothing to hide.

Known as the Transparent Man, he is a Circler who serves as the first person to wear a camera that continuously records and broadcasts his life.

An attractive Circler in her mid-thirties who works on YouthRank, an academic tracking program. She openly flirts with Francis during a broadcast, sparking a brief moment of jealousy in Mae.

An English fugitive wanted for a terrible crime. She is randomly selected during Mae's presentation and tracked down by a mob of Circle users in less than ten minutes.