This book centers around Tally, an Ugly who yearns to be a Pretty and cannot wait until her 16th birthday when that will happen. The youngest of all her friends, she is the last to have the operation that makes her beautiful: perfect doe eyes, full lips, hair that lies flat. But she meets Shay (with whom she shares a birthday) who tells her that being Pretty is not what it seems and tries to convince her to run away to a place called the Smoke, where people never have the Pretty operation. Tally, appalled at the thought of remaining Ugly for the rest of her life, balks and decides to remain in Uglyville. But the day of her birthday and right before her operation takes place, Special Circumstances takes Tally to the outskirts of town and tells her that she has to go to the Smoke before she can be turned into a Pretty. She eventually relents, traveling by hoverboard for days on end, searching for the Smoke from clues that Shay had left her in a note. Eventually she finds it and is initially appalled by them: full of Uglies, chopping down trees, eating wild animals, who would ever want to live that way? But slowly she learns more about the Smoke and the truth about what happens when you turn Pretty. She decides to stay in the Smoke and hurls the necklace that she was supposed to use to summon Special Circumstances into a fire. Unbeknownst to her, she accidentally calls Special Circumstances, who find the Smoke. Does Tally and her Smokey friends escape, or do they all turn into bubbleheaded Pretties?