However, after publishing the series' first three novels, Uglies, Pretties, and Specials, he ultimately wrote an additional fourth book, Extras.
In the post-apocalyptic future society where Tally lives, teenagers, upon reaching their sixteenth birthday, undergo a surgery to mold them into a so-called "Pretty."
Dr. Cable, the head of the mysterious Special Circumstances, cuts Tally a deal: betray her friends and help the city locate the runaways or remain an "Ugly" forever.
[2] When Tally joins the Smokies, she learns a chilling truth: the surgeries that the city performs are not just intended to render its inhabitants beautiful.
The city also puts lesions into the brains of the "Pretties", making them shallow, unintelligent, and ultimately an easier to control population.
The fourth novel centers on Aya Fuse, a girl struggling to find her place in the chaotic world after Tally frees people to think for themselves.
The new society is composed of about one hundred small post-scarcity, independently run city states, spread out across the seven continents, which now have different coastlines as a result of global warming.
In a promotional interview prepared by Westerfeld's publisher, Simon & Schuster, he talks about his inspiration for the series, stating: "We are definitely heading toward a world in which lots of people will get to decide how they look… [I] wanted to write a future in which these technologies were fairly common.
[4] Reviews noted the extensive similarities between the plot of the series and that of "Number Twelve Looks Just Like You", a 1964 episode of The Twilight Zone.
Uglies are encouraged to call each other nicknames based on their personal imperfections (e.g.: Fatty, Skinny, Squint, or Zits), as well as to use software to generate preferences for their facial features.
Unbeknownst to them, Uglies are also monitored by city authorities, not to restrain their behavior but to see which of them are most capable of 'pulling tricks' such as sneaking out at night and into New Pretty Town.
This information is used in the Uglies' later life to determine whether they are capable of holding jobs that require decisiveness, initiative, and independent thinking, such as being a surgeon, a firefighter or a Special.
The Operation completely overhauls a person's body structure and also includes lesions upon the brain, which makes them compliant and less likely to cause conflict.
They then move to the suburbs and are allowed to marry and have children, but are encouraged to do so only every 10 years, so as to discourage the formation of sibling bonds, and to ensure that the population of the city doesn't rise over capacity.
Specials are described as frighteningly beautiful and as a "cruel pretty" with features like large coal black eyes, sharp cheekbones ...etc.
They undergo a special surgery that gives them the ability to feel vibrations with their hands, enhanced senses, muscles sheathed with self-repairing mono filament, sharp orbital alloy teeth, incredible reflexes, bones made out of aircraft ceramics (light as bamboo and hard as diamonds).
The Surge (also called The Operation) is an internationally standardized and performed medical procedure mandated by the new society that plays a central part in the plot of the Uglies series.
The Surge consists of many steps, taking place over a single twenty-four-hour period, half of which is spent in anaesthetic stasis.
This surgery is entirely cosmetic (unless the pretty is entering a job which requires creativity and quick-thinking, in which case, some lesions are removed), and can be performed in an afternoon.
The Smokies, in partnership with another city, Diego, mass distributed the pills across the world, causing the "Mind Rain", which marked the end of the prettytime.
Daring, dangerous, or thrilling acts all cause the "bubbly" feeling, as well as physical pain and heightened emotional states, such as stress or interest.
Pretties who are self motivated enough to continue undertaking challenging actions can eventually cure their own brain lesions, which is considered a sign they are suitable for higher-skilled jobs, such as government positions, doctors, or Specials, once they become Middles.
Throughout the series, Tally undergoes significant changes physically and mentally from Ugly, to Pretty, to Special, different classes of citizen in her city.
The Smoke is an established camp in the wilderness, where runaways from cities gathered to avoid the lesions included in the pretty operation.
The Old Smoke was established by Maddy and Az (David's parents) in a remote location in the wilderness near railroad tracks and a forest.
Tally Youngblood accidentally alerted Special Circumstances when she threw her tracker pendant into a fire, as a show of trust and caring for David and The Smoke.
Diego supplies the Smokeys with the cure, sneak suits, a city to take refuge in, and removal of the lesions by a doctor in a safe hospital setting.
Also, the large mountain that Aya and the Sly Girls visit multiple times in the story is presumed to be Mount Fuji.
In September 2020, a feature film adaptation titled The Uglies was announced to be in development with 20th Century Fox and Joey King signed on to star in the lead role as Tally Youngblood.
[11] Later that year, Keith Powers, Brianne Tju, Chase Stokes, and Laverne Cox joined the supporting cast.