The series is based on the 2017 novel of the same name by Karen M. McManus and follows five high school students who enter detention, where one of them dies under suspicious circumstances and an investigation ensues.

It stars Mark McKenna as Simon, the deceased student, and Annalisa Cochrane, Chibuikem Uche, Marianly Tejada, and Cooper van Grootel as the main suspects, with Barrett Carnahan, Jessica McLeod, and Melissa Collazo, Sara Thompson and Alimi Ballard in supporting roles.

Simon, known for starting an online gossip group called About That with his friend Janae to snitch on his classmates, suffers a fatal allergic reaction.

A user called "Simon Says" tells Addy, Cooper, Bronwyn, Nate, and Janae that they must do as they say or a video proving they killed Jake will be sent to the police.

When they deduce that "Simon Says" is Fiona, Nate's tutor, she demands they hand over Addy, who pulled the gun's trigger and killed Jake.

In September 2017, Universal Cable Productions reportedly acquired the rights to One of Us Is Lying—the debut novel of Karen M. McManus—in a competitive situation and would produce a television series adaptation to be released on E!.

Madrona thought the show would provide something "a little brighter" than traditional mystery stories and found the novel "super addictive"—he was also intrigued by the flawed and untruthful characters, and saw the project as a chance to explore more profound themes of friendship, love and want.

Madrona found the idea of a single season that tells a complete story while solving the show's biggest mystery very satisfying.

[16] In October 2019, Marianly Tejada, Cooper van Grootel, Annalisa Cochrane, Chibuikem Uche, Jessica McLeod, Barrett Carnahan, and Melissa Collazo were announced as part of the cast.

According to producer Matt Groesch, the beaches on the country's east coast provided an excellent match to those in Southern California.

According to Deadline Hollywood, Peacock executives were satisfied with the show's creative output, but it was unable to attract the necessary viewership to support more seasons.

"[31] Brad Newsome, writing for The Sydney Morning Herald, said the story "deftly tweaks its balance of suspicions to keep things interesting, but it's McKenna and Van Grootel who really pull focus.

"[32] The Hollywood Reporter's Angie Han said the series was missing a spark to set it apart from similar programming, with characters that feel like "archetypes", a "sour, dour mood, with few moments of either levity or raw pain", and dull colors that "keep the show's emotions at arm's length".