Tally sneaks out from her bedroom in Uglyville across the old bridge to New Pretty Town to see her erstwhile best friend Peris. Peris' birthday is three months and two days before Tally’s, which means he has already undergone the extreme cosmetic surgery that transforms 16-year-olds from uglies into pretties. In New Pretty Town, Tally dons a pig mask that has been spit out of a passing drum machine, so as not to be spotted.
At Peris’ dorm, there is a white-tie party going on. Tally creates a stir as the only person there in a pig mask, and is therefore unable to maintain a low profile. She searches for Peris and eventually finds him alone in an elevator. He seems unhappy to see her but reticently confirms that they are still best friends, even though he has only written her once since turning pretty. Tally finds that her discarded pig mask has disintegrated into the elevator floor and so she must flee another way. At Peris’ suggestion, she uses a bungee jacket to jump off the roof of the dorm. At the last minute, she decides to pull the fire alarm, hoping it will distract the pretties. Instead, it creates a larger ruckus, sending hovercars and fire engines to the scene.
Tally hides in a pleasure garden while authorities search for her. There, she happens upon another ugly—Shay—who has hoverboarded over the river to New Pretty Town on her own secret expedition. Together, they narrowly escape New Pretty Town using the makeshift ladder Tally has attached to the old bridge.
Shay, now a friend of Tally’s, teaches her how to hoverboard. During the lesson, the two girls discuss their happiness at having found one another. They discover that they share the same birthday. Tally is overjoyed that she will not be abandoned to a lonely and ugly existence for even a moment by Shay. Shay does not seem as enthusiastic about undergoing the surgery as Tally is. She assures Tally that even if she turned pretty first, she would never abandon Tally. Tally concurs, but is doubtful. Many people make these promises, but few actually deliver on them.
In the next scene, Tally uses technology to show Shay a variety of options for how she’d like to look after her operation. Shay is not interested in this game, but Tally pressures her into creating her own pretty model, which makes Shay angry because she feels that Tally does not accept and love her for who she is. Tally explains that before the operation, inequality reigned as a result of people judging one another based on appearance. This is why the operation exists, as an equalizing force. Shay is skeptical. Tally abandons the game and agrees to go hoverboarding.
While hoverboarding, Shay pressures Tally to sneak out again, this time beyond the bounds of the city and to the Rusty Ruins—the ruins of an old city, one dating back to a time before there were pretties or uglies—a time when cosmetic surgery wasn’t mandated.
After nightfall, Tally and Shay hoverboard to the Rusty Ruins. Tally learns from Shay that hoverboards only work when there is metal in the ground, which is why they have to walk through stretches in their journey. In the city, there is a man-made steel grid underlying everything. Out in the wilderness, one must rely on what nature provides.
The ruins extend far beyond what Tally expected. The two girls explore the city. Their trip culminates in Shay showing Tally how to ride an abandoned roller coaster using her hoverboard. She fails to tell Tally that a part of the track is missing, and Tally believes for a minute that she will fall to her death, before the hoverboard catches her and the track resumes. Initially, she is angry at Shay for not telling her, but Shay explains that it was meant as a surprise, and she wanted to gift Tally the experience of not knowing what would happen, because it had been so fun for her when she first rode. The two reconcile, and Shay reveals to Tally, after making her promise to keep it a secret, that she learned about the rollercoaster from David, a man who lives outside the city and beyond the ruins.
Shay takes Tally to the ruins of a building, where she lights a safety sparkler to signal to David that she is there. They wait for a while, but no one comes, and Shay reluctantly agrees to go home to the city. Back at the river, Tally thinks she sees another sparkler go off in the distance, at the building they just left. She does not tell Shay, for fear that Shay will make her go back.
The narration opens with a comparison of the summer sky at sunset to the color of cat vomit—an introduction to a central theme of the book: not all that is aesthetically pleasing is in fact truly beautiful. As night falls, Tally feels that the night is “bottomless and cold.” These observations serve as signifiers of Tally’s emotional state. Bereft of her best friend, she has become lonely, sad, and unsure of their connection.
The old bridge Tally uses to sneak into New Pretty Town is built without the use of smart technology, which, according to Tally, renders it more trustworthy and durable. After everything else has fallen, she predicts, it will still be there. This is the book’s first instance of foreshadowing. The reader is to understand that this dystopian world is precarious, capable of instant collapse should its technology fail.
Sneaking into New Pretty Town feels to Tally like the plight of “a rock climber facing a sheer cliff.” Tally feels dwarfed by the enormity and difficulty of her task, as well as powerless against the structural principles by which her world operates.
The pig mask Tally dons in New Pretty Town parallels Tally’s self-perception—she feels ugly, undeserving, and greedy for her best friend’s attention. Tally goes on to explain the ideology behind the extreme plastic surgery all teenagers undergo in her society. She has been told that the facial and bodily structure into which she will be transformed will help in her survival because it will make her more appealing to others. People will believe her to be vulnerable and want to protect her. Because of her beauty, they will think she is healthy and subconsciously consider her to be a good candidate for reproduction. Indeed, when Tally is almost caught by a middle pretty warden looking for her, she almost gives herself up because she has been conditioned to trust and rely on them for support and protection.
In contrast to the borderline-unfriendly way in which Peris greets Tally, Shay exhibits warmth and excitement towards her. She thinks Tally is cool, despite her ugliness. These incidences of characterization introduce Shay as a sympathetic character and Peris as an unsympathetic character. Shay is a true friend, while Peris is not.
Scattered throughout are important pieces of information that tell us about the dystopian society in which the narrative takes place. As Tally learns to hoverboard, we learn that smart technology works by adapting to its user, using sensors to read bodily signals. Uglies are rarely ever referred to by their given names. Instead, they use nicknames that refer to those things that are ugliest about their bodies. Shay is called “Skinny” and Tally is called “Squint”. Uglies are thus conditioned to emphasize their imperfections, rather than their strengths.
Later, when the girls use a technological interface that allows them to experiment with how they’d like to look after the prettifying operation, we learn that, in this society, symmetry is prettier than difference. Before allowing for any alterations, the interface divides the face of the user into two sides, or images, and doubles each side. This step in the game literalizes the idea that there are two sides to every person, that we are complex, multifaceted beings fraught with conflicting values, beliefs, and virtues, capable of a vast array of emotionality and behavior. Shay chooses to base her altered appearance on the side of her face that looks angry; she values her fierce nature. Tally prefers the softer side of herself; she likes nicety, prefers to acquiesce. Their styles of play work as indirect characterization, proving that Shay is more of an independent thinker than Tally, who would rather conform. This valuation of symmetry also teaches us about the values of their world. Namely, conformity is prized above all else.
From the characters’ face-altering game, we understand that though people have a say in what they’d like to look like after the operation, the city has strict regulations that do not allow them to request extreme or exotic changes to their appearance. These rules vary according to city, and theirs is particularly strict.
While playing, Tally tells Shay that she believes pretties don’t want to visit after their surgery because they don’t want to have to look at ugly people, effectively blaming the problem on the uglies’ appearance, rather than the pretties’ behavior. Tally shows Shay a version of her face that looks like Cleopatra, and Shay suggests that Cleopatra was not particularly physically attractive. What was seductive about her was her cleverness. There are other ways to be appealing to people, she seems to be saying. One does not have to look a certain way to be loved.
Because she pulled the fire alarm and jumped off a building on the night they met, Tally is worried that Shay believes her to be more adventurous than she actually is. In fact, she is afraid to venture beyond the bounds of her small world into the wilds of nature. She admits to Shay that she promised Peris she would stay out of trouble until her operation, so that she could ensure she would get to be pretty and rejoin him in their new life. Shay is skeptical of Peris’ motives for asking Tally to make that promise. She believes that Peris may have said this so he wouldn’t get any more disruptive visits from his old ugly friend. If Tally doesn’t want to go, she says, that’s fine—she’ll go by herself. In the acquiescent manner we have come to expect from Tally, she gives in and decides to accompany Shay.
Shay wants to show Tally that there are other kinds of fun than the ones prescribed by their society. She shows Hallie how to hoverboard down rapids and on a rollercoaster, both of which Tally is surprised to find she enjoys. Unexpectedly, Tally finds joy in being away from the city, out in nature. She reflects that everything feels realer in the wilderness, electrifying in its majestic intensity and in the physical demands it makes on those who venture into it. It hasn’t ever occurred to her that the Rusties, or those who lived before the institution of the operation, enjoyed their lives, only that they suffered thankless existences, working in obscurity until their civilization fell and they died scrambling to get out. Without the various conveniences provided by smart technology, Tally realizes that she has to rely on herself and that self-reliance can make a person feel more capable and confident.
That Shay is in contact with David, someone who lives outside the strict parameters of their society, indicates that she is invested in alternative ways of living. Until now, she has hidden the secret of David from Tally, which suggests that she may have more secrets we do not yet know.
As part of a prank on the newest uglies, Tally teaches Shay to use a bungee jacket, a gesture which underscores the idea that their friendship is built on risk-taking. Later, Shay expounds further on her sacrilegious views during a trip to the beach. While Tally believes that being pretty is tantamount to being at peace with oneself, Shay contends that this standardization of appearance reflects a valorization of mindless conformity. That Tally accuses Shay of immaturity for this opinion—in Tally’s view, Shay just doesn’t want to grow up—reveals an important character detail about Tally herself: she is in a hurry to be older and wiser because she isn’t happy with who she is.