Pieces of Her
There are several noticeable differences between Netflix's Pieces of Her adaptation and Karin Slaughter's novel of the same name, but the overarching plot of the show stays true to the book's for the most part. One big exception? The ending. Slaughter's novel gives mother-daughter duo Laura (Toni Collette) and Andrea (Bella Heathcote) the ability to move on with their lives, while the series presents them—Laura in particular—an entirely new reason to keep looking over their shoulders.
Defending Jacob
Both versions of Defending Jacob end with a shocking accident, but the outcomes are different. The Apple+ series—starring Chris Evans, Jaeden Martell and Michelle Dockery—sees both Laurie and her accused murderer son Jacob survive, while he dies in the book penned by William Landay.
The Undoing
The question "Is Jonathan a murderer?" is the crux of HBO's entire series The Undoing, whereas in the book its based on, You Should Have Known, the answer is clear from the start: yes.
Nine Perfect Strangers
Not only is Carmel not Masha's shooter in the Liane Moriarty book—a huge twist that's dropped on the show's viewers toward the end of the season—but Masha's also never threatened by the calls and texts that exist in the Nine Perfect Strangers series. What is in the novel though? Frances and Tony getting married and Jessica and Ben breaking up.
13 Reasons Why
When a TV adaptation gets the multi-season treatment, it makes sense for new plots, characters and backstories to pop up. However, season one of Netflix's 13 Reasons Why stayed somewhat true to the novel of the same name by Jay Asher—that is, until the end. After listening to the tapes left behind by Hannah Baker, who died by suicide, book-Clay mailed them to the next person meant to listen and that's it, we never heard what happened next. On the show, Clay bypassed Bryce—a rapist in both versions—and handed the tapes over to the school counselor. Several new stories played out from there, and the season finale ended with Clay peacefully driving around with Tony and his childhood friend Skye, who, in the book, he doesn't reconnect with until the very end, once he realizes she's showing signs of being suicidal.
Game of Thrones
George R.R. Martin has yet to release the final two books of the A Song of Ice and Fire series, but he's publicly stated that they'll feature a different ending than the Game of Thrones TV series that had its finale in 2019.
The Haunting of Hill House
Eleanor has a tragic ending on Mike Flanagan's adaptation of The Haunting of Hill House, but in Shirley Jackson's book—which is significantly different and much darker than the Netflix series—all of the main characters have bleak endings.
Gossip Girl
There are too many differences between the OG Gossip Girl and the book series to count, but perhaps the most egregious is that Gossip Girl's true identity is never fully revealed in Cecily von Ziegesar's novels, while Dan Humphrey of all people is behind the blog on the show.
Little Fires Everywhere
The Richardson home burns to the ground in both the novel by Celeste NG and Hulu's adaptation, but while Izzy lights the little fires in everyone's rooms in the book, it's her three siblings that do it on the show. Additionally, the source material doesn't include the series' plot line of Mia taking Pearl to meet her maternal grandparents.
The Outsider
Both HBO and Stephen King's versions of The Outsider end with the entity known as El Cuco being destroyed—at least, that's what you think happened on the show until a mid-credits scene implies that El Cuco may be inhabiting Holly's body.