Jennifer Niven’s 2016 book, Holding up the Universe, is a young adult novel that explores the love story between two teenagers living in Amos, Indiana. The story follows Jack Masselin, a 17-year-old popular boy who secretly has a neurological disorder called prosopagnosia that inhibits his ability to recognize faces, and Libby Strout, a 16-year-old overweight girl who had to be lifted from her home by crane after a panic attack. The experience led to Libby being dubbed “America’s Fattest Teen.” As the story unfolds, Jack and Libby, realizing they have more in common than they thought, begin an unlikely romance. However, both teenagers grapple with their own complicated identities along the way, causing tension to arise in how they think of themselves and how they present themselves to others.

Jack and Libby narrate alternating chapters. The novel also occasionally moves forward or backward in time, as well. For example, beginning on page 164, the narration goes back three years in the past, to the night of Libby’s rescue from her home; on page 185, the action returns to the present. Jack and Libby narrate in the present tense and from a first-person point of view, allowing readers a close look into the thoughts of the two main characters as they navigate their identities and meet the mental, social, and emotional challenges of adolescence.

The novel begins with a letter from Jack to an unknown recipient in which he writes that he is about to do a “shitty thing” in order to “protect you and also myself” (15). In the letter, Jack describes his prosopagnosia, telling the recipient that he or she is the only other person to know about Jack’s disorder. The book then jumps eighteen hours into the past and shifts the narration to Libby, who describes her home-rescue incident and label of “America’s fattest teen.” Readers also learn of her mother’s untimely death, which Libby suggests triggered her extreme weight gain. After years of homeschooling, Libby is excited but nervous about beginning her junior year at Martin Van Buren High School the next day.

Over the next few pages, readers are introduced to Jack and Libby’s family and friends. Jack has two brothers, 16-year-old Marcus, and 10-year-old Dusty. His closest friends at school are Dave “Kam” Kaminski and Seth Powell, both of whom share Jack’s reputation as a popular but perhaps callous “jock.” Jack has an “on-again, off-again everyone-assumes-we’ll-end-up-together-forever” (23) relationship with Caroline Lushamp, one of the most beautiful and popular girls at school, although their relationship is strained by Jack’s secret inability to recognize her face.

Readers learn that Libby has a very close relationship with her father, whom Libby says often unfairly receives the media’s blame for letting her become morbidly obese. Initially, she has no friends when she returns to school but quickly reunites with Bailey Bishop, a kind girl she knew from her time in public school years ago. Libby also befriends Iris Englebrecht, another overweight girl who becomes the first target of Seth, Kam, and Jack’s cruel “Fat Girl Rodeo” game. In Fat Girl Rodeo, a person non-consensually throws themselves onto a so-called “fat girl’s” back and holds on for as long as possible. The game is cruel, and while Jack’s friends find it funny, Jack does not. But because he worries about losing the people he can recognize, he goes along with the game anyway.

Libby becomes the next target of the rodeo when she attempts to confront Kam about his assault on Iris. The next day at lunch, Jack jumps on Libby as part of the game, but Libby throws him off, punching him in retaliation. The two are called into the principal’s office where they are required to do community service and attend an after-school Conversation Circle with the school counselor, Mr. Levine. That night, Libby discovers that Jack slipped his letter about prosopagnosia into her backpack during their scuffle; she decides to write back to him.

The action then flashes back three years, to the night Libby was rescued from her house via a crane and taken to the hospital. Readers learn that Jack lived across the street and witnessed the entire event. The day after the rescue, Jack sneaks into the Strouts’ house and takes a magnet and a copy of Shirley Jackson’s We Have Always Lived in the Castle, Libby’s favorite book. He decides to mail the book to her hospital room, along with a note in which he writes, “I want you to know I’m rooting for you.”

Back in the present, Libby begins to receive a stream of nasty notes in her locker taunting her and telling her, “You aren’t wanted” (251). She contemplates withdrawing from school, but her spirits are lifted when a vacancy suddenly opens up on the school’s drill team, the Damsels. Meanwhile, Jack and Libby continue to meet for the daily Conversation Circle and begin discussing Jack’s prosopagnosia in private. Libby encourages Jack to tell someone else about his condition. Jack continues to keep it a secret but follows Libby’s advice to learn more about it on the Prosopagnosia Research Centers’ website. There, he discovers that he may be able to receive an official diagnosis from the researchers at Indiana University, in Bloomington. Jack, who finds himself beginning to develop feelings for Libby, invites her to accompany him to the university to meet with Dr. Amber Klein, who may be able to confirm his self-diagnosis. Libby agrees, contemplating whether she also wants to be tested for the genetic aneurysm that killed her mother.

Dr. Klein confirms that Jack has severe prosopagnosia, explaining that while there is no cure, people who suffer from the disorder may be able to develop strategies for more effectively identifying people. Meanwhile, Libby decides not to get tested for the aneurysm following her friend Jayvee’s advice that “the not knowing is something too” (307). Over the next several days, Jack and Libby continue to grow closer, developing romantic feelings for one another. However,Howev

 Jack’s prosopagnosia continues to cause him problems, and he finds it increasingly difficult to keep it a secret. Thinking Libby would have to remain overweight in order for him to recognize her, Jack breaks up with Libby, telling her, “I’d never be able to see you” (394).

After he mistakes his now ex-girlfriend, Caroline, for another girl for the second time, Jack decides that he can no longer keep his condition a secret and announces to his friends and family that he has prosopagnosia. Likewise, Libby fully embraces herself as she comes to terms with both her imperfections and her mother’s death. As the novel draws to a close, Jack begins to think about this supposed flaw as part of his identity similar to how Libby thinks of her weight. He finally chooses to be imperfect, which also helps him realize that he is in love with Libby. The two meet at the park, and after Jack apologizes for his poor behavior, he tells Libby he can see her in a way he cannot see anyone else. They confess their love for each other as the novel concludes.