One Of Us Is Lying: 7 Big Differences Between The Book And The Peacock TV Show

Cooper, Bronwyn, Addy, Maeve and Janae in One of Us Is Lying.
(Image credit: Peacock)

Spoiler alert! This story contains spoilers for One of Us Is Lying — both the Peacock TV series and the book. Consider yourself warned!

The One of Us Is Lying TV series, now on Peacock, is based on a book of the same name by Karen M. McManus. The plot is deceptively simple: Five students walk into detention; only four come out alive. It’s quickly deduced that the murder of Simon Kelleher — maligned creator of Bayview High's gossip app About That — could only have been committed by one of the other students in the room. Anytime a book is developed into a TV show or movie, you run the risk of having key facts changed, and particularly with a murder mystery, it begs the question of how loyal the series stayed to the source material.

While the Peacock show hit a lot of the main notes of Karen M. McManus’ book, there were some very significant differences — including the ending. So, viewers who read One of Us Is Lying still got to enjoy the whodunnit of it all when they watched the new series. How did it all go down in the book? Let’s take a look at seven of the biggest differences between One of Us Is Lying the book and the TV show.

Simon looks over his computer in One of Us Is Lying

(Image credit: Peacock)

Jake Didn’t Kill Simon In The Book

The biggest difference between the series and the book is the answer to the question, “Who killed Simon Kelleher?” In the Peacock series, Jake and Simon concocted a “prank” where Simon would knowingly ingest peanut oil and have an allergic reaction to revenge-scare his classmates, before being saved by an epi pen from the nurse’s office. But, Jake got spooked when Simon said he had recorded their conversations, and he stole the epi pens. Simon died from his allergic reaction, leaving Jake to taunt the Bayview Four on Simon’s About That app and frame them for the murder.

The book’s ending was arguably darker, and that’s saying something. While Jake still helped to continue About That after Simon’s death, in the book Simon died by suicide. He had become obsessed with school shootings and wanted to do something more creative — ruin his enemies’ lives by framing them for his murder. In the book, Simon enlisted Jake’s help in stealing the epi pens so there’d be no way to save him, with instructions to plant them on one of the other four students. Simon being the mayor’s son was added for the series, although it wasn’t used as a particularly important plot point.

Mrs. Avery in One of Us Is Lying

(Image credit: Peacock)

The Detention Teacher Had No Role In Simon’s Death

In the series, Simon blackmailed Mrs. Avery to get the Bayview Four into detention with him that day. He said he was going to reveal that she helped Vanessa get an abortion. In the book, the detention teacher was Mr. Avery, and he played no role in Simon’s death. Whereas Simon paid streakers to get Mrs. Avery out of the room, in the book he paid students from another school to stage a fender bender for the same purpose.

Simon and Maeve smile at each other in a flashback in One of Us Is Lying

(Image credit: Peacock)

Maeve Was Not Involved With Simon Or Janae

In the book, Maeve was still the gang’s tech guru, but the series added her romantic tie-ins to Simon and Janae. Even without a romantic involvement, Bronwyn still did have reason to confront (and threaten) Simon over an About That post concerning her sister, though. In the book, Maeve showed up on the app after getting drunk at a party, not for sexting like in the Peacock TV show. Also, in the series, a rift formed between Simon and Janae over their mutual attraction to Maeve, while in the book, they were fighting because Janae refused to help Simon with his suicide plan. 

Janae in One of Us Is Lying

(Image credit: Peacock)

Janae Knew All About Simon’s Plan

That’s right. In the book, Janae knew everything. She had become worried about Simon the deeper he got into 4chan talking about school shootings and mass killings, and she refused to go along with his plot. That was when Simon brought in Jake to take over About That after his death. Jake got a conversation with Janae on tape and edited it to make it sound like she was guilty, thus blackmailing her into compliance. 

As the Bayview Four (a.k.a. Murder Club) worked to prove their collective innocence, Addy began to suspect that Janae knew more than she let on. Addy confronted Janae, asking if Simon had planned to kill himself. Janae broke down, telling her everything, and that was when Jake showed up and chased Addy into the woods. Addy and Janae were both injured before Cooper saved them, and Jake was arrested, not killed, like in the series.

Keely and Cooper celebrate after a baseball showcase in One of Us Is Lying

(Image credit: Peacock)

Cooper’s Outing Was A Much Bigger Deal

In the Peacock version of One of Us Is Lying, Cooper’s brother and girlfriend, Keely, already knew he was gay. But in the book, Cooper was 100% in the closet, and he suffered major repercussions when the police outed him during their investigation. Keely was blindsided, MLB scouts and colleges stopped calling, and hecklers started showing up to Cooper’s baseball games. And, while Cooper’s dad didn’t react well to his son’s coming out in the series, he was much more homophobic in the book.

The manner in which Cooper’s About That post got changed was also worse in the book. In the series, Simon said it went against his moral code to out people, and Janae changed the post for the same reason. In the book, it was Jake who changed the post, but only because he was ashamed that his best friend was gay. Cooper’s scandal in Mississippi was not part of the book.

Kris and Cooper smile for a selfie in One of Us Is Lying.

(Image credit: Peacock)

Kris Was A Minor Character

Because Cooper was not out in the book, his boyfriend, Kris, was not seen as much, at least until the end. In the series, Kris knew Nate (Nate was his dealer, naturally), and Kris even went to Cooper’s baseball showcase “in straight cosplay.” In the book, Kris knew that Cooper was in high school and was not out — important details that caused the couple to temporarily break up in the series. Interestingly, even though his role was small, it was actually Kris who, in the book, connected the dots about Simon being depressed and carrying out the dark suicide plot. 

Nate and Bronwyn share a moment in One of Us Is Lying

(Image credit: Peacock)

Nate And Bronwyn Were More Of A Thing

When the series opened, Bronwyn was dating Evan from her debate team. In the book she did have a crush on Evan, but as soon as Simon died, Bronwyn became immediately interested in Nate. The burner phones that they used to communicate, late-night movie watching and escaping from the media on Nate’s motorcycle were all hinted at in the series, but the book let the budding romance develop a lot more deeply. While they still butted heads in the book, they ended up together at the end, unlike in the series.

Peacock hasn’t announced if One of Us Is Lying will be back for a second season, but Karen M. McManus is prepared if they do. One of Us Is Next is the sequel to One of Us Is Lying and follows Maeve a year after the original book’s events, as someone starts a dark game of Truth or Dare at Bayview High. While we wait to see what happens with that, Season 1 of One of Us Is Lying can be streamed (opens in new tab) in full by subscribers to Peacock Premium.

Heidi Venable
Content Producer

Mom of two and hard-core '90s kid. Unprovoked, will quote Friends in any situation. Thrives on New Orleans Saints football, The West Wing and taco trucks.