This post contains spoilers for We Were Liars.

The lone body of a woman on a beach is rarely a good sign—just ask the affluent characters of Netflix’s The Perfect Couple or HBO’s Big Little Lies. That same holds for Prime Video’s We Were Liars, an eight-episode TV adaptation of the mystery YA novel published in 2014, but popularized via BookTok in 2020.

Both E. Lockhart’s book and the series from showrunners Julie Plec (The Vampire Diaries) and Carina Adly Mackenzie (Roswell, New Mexico), begin with heroine Cadence Sinclair Eastman (Emily Alyn Lind) washed ashore outside of her family’s secluded property on a private island off the coast of Martha’s Vineyard. The eldest grandchild of wealthy media mogul Harris Sinclair (David Morse) and his wife, Tipper (Wendy Crewson), doesn’t know how she got there, where her clothes went, or why none of her similarly-aged cousins, who call themselves the Liars, can give her any clarity.

The show cuts back and forth between Cadence’s post-traumatic amnesia and the events that led up to it the previous summer. Her mother Penny (Caitlin FitzGerald) has forbidden Cadence’s aunts Carrie (Mamie Gummer) and Bess (Candice King) from speaking about the incident. Also sworn to secrecy are the Liars: Carrie’s son Johnny (Joseph Zada), Bess’ daughter Mirren (Esther McGregor), and Gat (Shubham Maheshwari), the nephew of Carrie’s longtime boyfriend Ed (Rahul Kohli). But familial infighting soon gives way to secrets about the Sinclair dynasty—and insight about Cadence’s fate.

Ahead, a look at the biggest differences between the We Were Liars book and TV adaptation, from more insight about Johnny’s sexuality to a new twist on that shocking ending.

A Missing Timeline and Character

The original novel chronicles multiple summers, named for how old Cadence is during each season. Cadence and Gat begin to fall in love during summer 14. Grandmother Tipper dies before summer 15—the same year of Cadence’s accident. In summer 17, Cadence returns to Beechwood Island searching for answers about the previous year. But the show condenses the story into just two timelines: before Cadence’s accident, and after. All of major plot points take place in summer 16, including Grandmother’s sudden death from heart failure.

In the TV series, there’s also a major character missing from the Sinclair family tree. That would be Taft, the youngest son of Bess Sinclair. In the book, Taft’s main contribution to the story is his concern over Cadence’s Percocet addiction—a worry that gets doled out to a slew of other characters on the show.

The Sinclair Sisters

Lockhart’s novel skims over the backstories of sisters Carrie, Penny, and Bess, the mothers of three of the titular Liars. There’s more information about them in the 2022 prequel, Family of Liars. That book is where Rosemary, “the daughter who didn’t grow up,” is first mentioned. But the series outright references their late sister, a fourth Sinclair daughter who died during childhood. She may have died due to something that happened during one of their own summers on the island—while grieving the death of her own daughter in the show’s season finale, Bess wonders if the fire is “punishment” for “what we did.”

Candice King, David Morse, Wendy Crewson, Mamie Gummer, Caitlin Fitzgerald in We Were Liars.Jessie Redmond