<p>Similarities</p>
Anna and Jack’s daughter Charlotte dies from “crib death.”
Alice Andrews pretends to have dementia.
Priya is the only sound detective in the case.
Rachel, Helen, Zoe and Catherine die.
The Differences<br/>
In the book, the setting is a dreary town in a British village, and certain parts take place in the city of London. The TV series is set in Georgia, specifically in the bustling news anchor area of Atlanta and the hometown of Dahlonega, Georgia.
The Characters:
Anna Andrews is a functioning alcoholic in the novel. She’s constantly needing just one more sip to drain the whole bottle. She always has mini bottles stashed whenever she needs release from her cruel past. In the series, Anna is shown at the beginning downing the rest of a white wine, but never touches an ounce of alcohol throughout the duration of the show. She is almost painstakingly put together.
Detective Jack Harper is kind of losing it in the book. He is back to living with his sister and niece after losing his job in London and his marriage to Anna. He’s sloppy with his work and personal life. Having a one-sided affair with the fatal victim, Rachel, since his divorce from Anna. In the series, Jack is a thoughtful, considerate Uncle and a slightly reckless driver. He and Anna have an estranged marriage, and his jealousy over Anna is one that translates through both versions.
Zoe, Jack Harper’s sister. She is an average mother who does her best for her daughter. In the series, they make her out to be a heavy drinker and a terrible mother. In both, they are curious about the murders being connected and ultimately are correct.
Catherine Kelly/Cat Jones is overweight and goes through traumatic bullying by the friend group of Rachel, Zoe and Helen. In the series, Lexy has an extended character story of how she seemingly killed her sister by exhausting her asthma inhaler while on a family outing. Giving her a backstory for that of a killer.
Clyde Duffie, Rachel’s husband, was rarely ever mentioned or heard from in the book. He was an older man and somewhat senile. In the series, he is a middle-aged man who was considered a key part of the suspect list. Clyde had a motive of blackmail toward his wife and his wife’s friend Helan Wang.
In the book, the ending is extended and twisty. They both ultimately end up at the childhood home or lakehouse (tv series) of Catherine/Lexy. It’s at the Lakehouse that Anna puts the pieces together that Lexy is actually Catherine, the girl the friend group bullied and abused. In the book, Anna already has an intuition that Cat Jones is the revamped Catherine. This is where the differences take place, but lead to the same conclusion of Priya shooting Catherine dead. All the evidence led to Catherine being convicted of the killings.
However, in the book, Alice’s mother arrives when all chaos is breaking loose, and in that moment, she confesses she killed her father in self-defense. Deeming this as dementia, Anna brushes it off. Later on, Alice writes a full confession in a letter that is read through in both versions and unveils that she is the rightful killer of Rachel, Helen and Zoe. She admits to killing Anna’s father and burying him in the backyard in the book only. Otherwise, her tales of faking her dementia to make her seem unsuspecting and the reasoning behind the killings are mirrored.