Book Summary Contents
- 1 Introduction: What Is One of Us Is Lying About?
- 2 Quick Summary
- 3 One of Us Is Lying Summary & Analysis & Review & Plot Summary
- 4 5 Big Questions This Book Answers
- 5 Who Are the Main Characters in One of Us Is Lying?
- 6 What Are the Major Themes in One of Us Is Lying?
- 7 What Makes This Book So Addictive?
- 8 What Do Readers and Reviewers Say?
- 9 One of Us Is Lying Summary By Chapter (1–30 Summary)
- 9.1 Chapter 1
- 9.2 Chapter 2
- 9.3 Chapter 3
- 9.4 Chapter 4
- 9.5 Chapter 5
- 9.6 Chapter 6
- 9.7 Chapter 7
- 9.8 Chapter 8
- 9.9 Chapter 9
- 9.10 Chapter 10
- 9.11 Chapter 11
- 9.12 Chapter 12
- 9.13 Chapter 13
- 9.14 Chapter 14
- 9.15 Chapter 15
- 9.16 Chapter 16
- 9.17 Chapter 17
- 9.18 Chapter 18
- 9.19 Chapter 19
- 9.20 Chapter 20
- 9.21 Chapter 21
- 9.22 Chapter 22
- 9.23 Chapter 23
- 9.24 Chapter 24
- 9.25 Chapter 25
- 9.26 Chapter 26
- 9.27 Chapter 27
- 9.28 Chapter 28
- 9.29 Chapter 29
- 9.30 Chapter 30
- 10 Author Spotlight: Karen M. McManus
- 11 Conclusion: One of Us Is Lying Summary & Analysis & Review & Plot Summary
- 12 Get Your Copy
- 13 Attachments & References
Introduction: What Is One of Us Is Lying About?
One of Us Is Lying Summary dives into a chilling murder mystery wrapped in the lives of five high school students. On a seemingly normal Monday afternoon at Bayview High, five students enter detention, but only four walk out alive. Simon, known for running the school’s gossip app, dies mysteriously. Soon after, it’s revealed he was planning to post explosive secrets about his classmates—making each of them a suspect.
This addictive young adult thriller by Karen M. McManus blends the tension of a classic whodunnit with a modern coming-of-age twist. With comparisons to Pretty Little Liars and The Breakfast Club, the story explores how far someone would go to protect their secrets—and what it really means to be guilty.
Quick Summary
One of Us Is Lying Summary & Analysis & Review & Plot Summary
The novel begins with five students entering detention for a reason none of them seem to understand—each found with a phone that isn’t theirs. During detention, Simon drinks from a water cup, suffers an allergic reaction, and dies. Suspicion arises quickly when investigators learn Simon was about to release secrets that could destroy the reputations of the other four students.
Secrets Revealed:
Each student’s secret leaks:
- Bronwyn cheated on a major exam.
- Nate is still dealing drugs.
- Addy cheated on her boyfriend.
- Cooper is secretly gay.
As pressure mounts, the students form an unlikely alliance, dubbed “The Murder Club.” They work together to uncover the truth while dealing with media attention, peer scrutiny, and their own personal transformations.
Eventually, they uncover the shocking twist: Simon’s death was a suicide—a well-orchestrated plan to frame the others. With help from a co-conspirator, Simon’s twisted need for control and drama led to his fatal end.
5 Big Questions This Book Answers
- How far would you go to protect your secrets?
- What happens when your identity is exposed to the world?
- Can people truly change under pressure?
- What is the line between truth and gossip?
- How do teens navigate betrayal, loss, and social expectations?
Who Are the Main Characters in One of Us Is Lying?
Bronwyn Rojas – The Brain
- Straight-A student
- Yale hopeful
- Rule-follower with a shocking secret
Nate Macauley – The Criminal
- Already on probation
- Deals drugs to survive
- Misunderstood and more complex than he appears
Addy Prentiss – The Beauty
- Homecoming princess
- In a controlling relationship
- Faces a powerful transformation
Cooper Clay – The Athlete
- Star baseball pitcher
- Hiding a life-changing truth
- Struggles with identity and acceptance
Simon Kelleher – The Outcast
- Creator of Bayview High’s gossip app
- Loved and hated for his brutal honesty
- His death is the mystery that unravels them all
What Are the Major Themes in One of Us Is Lying?
1. Secrets and Truth
Every character hides something, but the book shows how the truth eventually finds its way out. Secrets define high school life in the story, but also reveal the deeper emotional struggles each teen faces.
2. Peer Pressure and Identity
Conforming to expectations leads to self-betrayal. Addy’s journey, in particular, highlights how we often live for others until we break free.
3. Social Media and Modern Gossip
Simon’s app symbolizes today’s obsession with online reputation. The story explores how a single post can destroy lives—and how we treat scandal as entertainment.
4. Mental Health Awareness
Simon’s suicide brings up issues of depression, loneliness, and the consequences of untreated mental illness. The book subtly critiques how these signs are often missed or dismissed.
5. Justice and Redemption
Though wrongly accused, the four teens find a new sense of self. Justice isn’t just legal—it’s personal, emotional, and social.
What Makes This Book So Addictive?
Realistic, Relatable Characters
McManus skillfully uses YA stereotypes only to subvert them. Bronwyn isn’t just the smart girl—she’s under family pressure. Nate isn’t just a bad boy—he’s neglected and alone. Addy isn’t shallow—she’s trapped. Cooper isn’t just a jock—he’s grappling with identity.
A Clever, Layered Mystery
Fans of mysteries love this book not just for its twist, but for the red herrings, the suspenseful pacing, and the psychological depth. While some readers may predict the ending, the story’s emotional resonance keeps them hooked.
Non-Cliché Ending
Rather than tying everything up with a bow, McManus offers a messy, real conclusion. Mistakes are made. Growth happens. Some questions linger.
Cinematic and Fast-Paced
No wonder it was adapted into a TV show. The book reads like a series, with sharp scenes, cliffhangers, and character arcs that could fuel multiple seasons.
What Do Readers and Reviewers Say?
- “It felt so addictive, I couldn’t put it down.”
- “One of the best YA thrillers I’ve read in years.”
- “The characters were so vivid and relatable.”
- “This book blew me away—I thought I had it figured out, but I was wrong!”
- “There are deeper messages under the mystery. I appreciated the discussion on mental health and identity.”
While some reviewers noted that the twist could be guessed early, most praised the storytelling and character development more than the reveal.
One of Us Is Lying Summary By Chapter (1–30 Summary)
Chapter 1
Five students — Bronwyn, Nate, Addy, Cooper, and Simon — land in detention. Simon, creator of the school gossip app About That, drinks water and suddenly collapses. He dies from an allergic reaction, and no EpiPens are found in the nurse’s office.
Chapter 2
Shock spreads through Bayview High. The four remaining students are considered suspects. Each begins reflecting on what happened and the secrets Simon might have exposed.
Chapter 3
Details about Simon’s app surface. He had a scheduled post set to reveal damaging secrets about all four students in detention. Everyone starts to wonder: who had the most to lose?
Chapter 4
The police open a criminal investigation. Each of the Bayview Four is interrogated. Officer Budapest takes the lead in questioning.
Chapter 5
Relationships start to strain. Bronwyn and Nate begin interacting more. Addy grows anxious, feeling the pressure from Jake and her mother. Nate shows some sympathy toward Bronwyn.
Chapter 6
Simon’s funeral takes place. His mom chooses Jake to be a pallbearer. The funeral is awkward, and rumors swirl. The four suspects become more isolated from the rest of the students.
Chapter 7
A post from an anonymous Tumblr account appears, claiming that Simon’s death wasn’t an accident — someone removed the EpiPens on purpose. The post hints the killer was in detention.
Chapter 8
More about each character’s secret is revealed:
Bronwyn cheated on an exam.
Addy cheated on Jake.
Nate is a known drug dealer.
Cooper’s sexuality is not public.
Chapter 9
The investigation intensifies. Police search lockers and question students. Janae, Simon’s best friend, appears emotionally fragile. Bronwyn worries about her reputation and college prospects.
Chapter 10
Nate gives Bronwyn a ride home. Their bond starts forming. Addy confides in her sister, Ashton. Cooper’s father becomes more controlling, suspecting his son is hiding something.
Chapter 11
Addy has flashbacks of her controlling relationship with Jake. She begins feeling increasingly guilty about her cheating. Maeve, Bronwyn’s sister, helps her dig into About That posts.
Chapter 12
Bronwyn visits Nate’s house. She learns about his troubled family situation and sees how different their worlds are. Nate becomes more humanized in Bronwyn’s eyes.
Chapter 13
Another Tumblr post hints at secrets still to be revealed. Janae distances herself from the others. Addy begins questioning how well she knew Simon.
Chapter 14
Police discover Simon’s next scheduled post: Cooper is allegedly using steroids. This devastates Cooper, especially as scouts and college prospects begin to lose interest.
Chapter 15
Cooper maintains a lie about steroids to avoid revealing he’s gay. He continues pretending to date Keely. The pressure is immense, especially from his dad.
Chapter 16
Bronwyn finds the courage to contact a nonprofit legal group called Until Proven. She meets Eli Kleinfelter, who agrees to help her if needed.
Chapter 17
Addy breaks down and finally admits to Jake that she cheated. He reacts angrily and ends their relationship. Addy begins to feel liberated for the first time.
Chapter 18
Maeve uncovers metadata proving Simon’s last posts were uploaded after his death, pointing to foul play. The four begin to consider that someone framed them.
Chapter 19
The Bayview Four start unofficially working together. They begin comparing timelines and details to figure out what really happened in detention.
Chapter 20
Nate and Bronwyn kiss. Their relationship deepens. Nate’s walls begin to break down. Bronwyn confesses that she stole exam answers to get into Yale.
Chapter 21
Addy begins transforming — cutting her hair, spending time with Janae, and thinking independently. She regrets allowing herself to be controlled for so long.
Chapter 22
Cooper’s secret relationship with Kris is revealed to the group. They’re supportive. He starts considering coming out, but his fear of family rejection holds him back.
Chapter 23
Cooper and Keely stage another date to maintain appearances. Keely starts to suspect the truth and becomes distant. Kris encourages Cooper to be honest.
Chapter 24
The police get closer to Cooper, believing the steroid claim. Maeve and Bronwyn realize that Cooper’s real secret wasn’t the one in Simon’s original draft.
Chapter 25
Bronwyn starts suspecting that Simon might’ve planned something darker. They uncover disturbing posts online showing Simon’s fascination with school violence and revenge.
Chapter 26
Addy becomes more assertive. She challenges her mother’s shallow priorities and reconnects with Ashton. She begins working at a local salon.
Chapter 27
Bronwyn learns that Simon had written out full posts about all four of them, but only some were posted. This inconsistency raises more questions.
Chapter 28
Nate’s mom returns after years of absence. He reacts harshly, feeling abandoned and betrayed. He had lied to everyone, saying she was dead.
Chapter 29
Maeve digs deeper into Simon’s online presence. She uncovers chats that point to him orchestrating the whole plan and possibly collaborating with someone.
Chapter 30
The Tumblr account hints that Simon might have helped stage his own death. The Bayview Four grow more certain that someone close to Simon helped him and is still hiding the truth.
Author Spotlight: Karen M. McManus
Karen M. McManus is a #1 New York Times bestselling author known for her captivating young adult thrillers. One of Us Is Lying was her breakout debut and has since become an international phenomenon, translated into 42 languages and adapted into a TV series. Her background in journalism and passion for storytelling shine through in her sharply crafted plots and realistic characters.
Other works include:
- Two Can Keep a Secret
- The Cousins
- You’ll Be the Death of Me
- Nothing More to Tell
- Such Charming Liars
McManus has earned a reputation for creating page-turners that appeal to both teens and adults. She writes with a strong understanding of teen psychology, social issues, and the real-world impact of secrets and lies.
Website: www.karenmcmanus.com
Instagram: @writerkmc
Conclusion: One of Us Is Lying Summary & Analysis & Review & Plot Summary
Should You Read One of Us Is Lying?
Absolutely. If you’re looking for a YA thriller that combines suspense, real-world issues, and unforgettable characters, this book is for you. It’s more than a murder mystery—it’s a mirror into the complicated lives of teenagers trying to survive high school, secrets, and societal pressure.
Try this twisty, emotional ride today—and discover why everyone’s talking about One of Us Is Lying!
Get Your Copy
Attachments & References
- Amazon’s book page
- Goodreaders’s book page
- Author’s image source: camd.northeastern.edu
- Book Cover: Amazon.com
- Quotes sources: Goodreads
