Tally is a 15-year-old "ugly" living in Uglyville, eagerly awaiting her sixteenth birthday to undergo the mandatory operation that will make her a "pretty." Characterized by her mischievous streak and tendency to play tricks, she initially believes completely in her society's superficial rules. Her deep loyalty to her friends forces her into a dangerous journey into the wilderness.

Shay is a rebellious teenager who shares Tally's birthday but completely rejects the city's obsession with physical perfection. Slender with dark hair and wide eyes, she values personality and individuality over conforming to the "pretty" aesthetic. Her decision to flee to the wilderness rather than undergo the mandatory surgery spurs the novel's main events.

David is a young man born in the wild, completely outside the city's influence and surgical mandates. He possesses a confident demeanor, a high forehead, and a crooked smile. Because he grew up removed from the city's aesthetic programming, he judges people by their actions and character rather than their physical appearance.

Dr. Cable is a cruel and intimidating woman who operates within Special Circumstances, an elite faction of "pretties" with enhanced physical traits. She possesses a hooked nose, sharp teeth, and a predatory demeanor that immediately distinguishes her from average citizens. She ruthlessly manipulates teenagers to protect the city's secretive status quo.

Maddy is David's mother and a former medical professional from the city. She fled the restrictive society alongside her husband to establish a free settlement in the wilderness. Having reversed her own cosmetic enhancements to live as an "ugly," she actively works to recruit city teenagers and build a community based on truth and solidarity.

Az is David's father and Maddy's husband, who previously worked as a medical professional in the city. He shares his wife's commitment to building a free society away from the city's control. He lives apart from the main settlement of runaway teenagers to prepare for potential retaliation from the city authorities.

Peris is Tally's childhood best friend who is a few months older than her, meaning he undergoes the "pretty" operation first. Once a mischievous partner in crime who shared a blood pact with Tally, his personality and priorities shift noticeably after his surgery. He fully embraces his new social status and dismisses his past life as an "ugly."

Croy is a teenager from the city who runs away to the wilderness settlement. Observant and cautious, he pays close attention to the supplies and timelines of new arrivals, prioritizing the safety of the hidden community.

Boss is an older "ugly" in his forties who lives in the wilderness settlement. He serves as a librarian and fiercely protects a collection of old magazines and artifacts from the previous, destroyed civilization.

Ellie is Tally's mother, an adult "pretty" living in the city. She holds naive, conventional views about the society's rules and attempts to comfort Tally when her mandatory surgery is unexpectedly delayed.

Sol is Tally's father, an adult "pretty" living in the city. Alongside his wife, he relies on the city's provided comforts and struggles to understand Tally's complicated situation with Special Circumstances.

Tonks is a ranger who operates outside the city limits. He and his team use ancient helicopter technology to perform controlled burns on parasitic, genetically engineered white orchids to protect the local ecosystems.

Sussy is a young "ugly" living in the city who is eager for excitement and rebellion. She is easily impressed by bold stunts and willingly agrees to assist runaway teenagers with a massive prank.

An is a rebellious teenager residing in Uglyville who spots suspicious activity in the ruins. He eagerly volunteers to participate in a large-scale distraction against the city.

Dex is a city-dwelling "ugly" who encounters infiltrators from the wilderness. Seeking adventure, he agrees to help execute a distraction against the city authorities.

Astrix is a runaway teenager who successfully escapes the city's strict control. She joins the hidden community in the wilderness to avoid the mandatory surgical procedures.

Ryde is a teenager from the city who chooses to flee into the wild. He embraces the difficult outdoor lifestyle to maintain his individuality and freedom.