Book Review: Killing Sadie by Rachel Peterson

Killing Sadie by Rachel Peterson

Content Warnings:

TW: murder, murder investigation, cheating, blood, alcohol, drugs, family loss, mental health. Readers 14+.

Publishing Date: August 13th, 2026
Publisher: Simon Pulse
Genres: Young Adult // Mystery, Thriller
Quick Thoughts: The story had this almost confessional, spotlighted way of pulling the reader into the past within the story, taking us along for the mystery. This was an adrenaline-fueled ride that commands your attention from the get-go. I cannot wait to read more from Rachel!
Rating:

Gifted/PR

I was gifted this book via the Publisher. All views/opinions are my own. I remain entirely impartial.

Literary Trope Guide

Party-gone-wrong

Who’s lying?

Unreliable POVs

Murder Mystery

about this book
Perfect for fans of How to Survive Your Murder and Dead Girls Can’t Tell Secrets, this young adult thriller unspools the truth behind a tragic murder through multiple unreliable narrators who all have secrets to keep.
Here’s what we do know: there was another infamous barn party at the McClain family farm last night, and things went horribly wrong. By the end of the night, there were two dead bodies in the old barn: seventeen-year-old Sadie Cooper and her killer, Mason Vreeland. The murder was heartbreakingly witnessed by Sadie’s twin sister, Jayne, and Sadie died in her arms. Mason was killed by Sadie’s boyfriend, Ben, in an attempt to save Sadie.
Aside from figuring out Mason’s motive, it should be an open and shut case.
But it’s not.
The story unfolds just after the murders, and Jayne, Ben, and Sadie’s best friend, Liz, are telling the cops what transpired at the party and the events leading up to it. But little details don’t match. And those little details start to add up to big discrepancies. But who’s lying, and why?
The shocking truth is revealed in the third act, when the POV shifts to victim Sadie herself, in the days leading up to the party. Witness exactly what happened—and see if you can piece it all together. Because poor Sadie totally missed what was right in front of her.

My Review

Thrillers are some of my favourite things to reach for when I want something to disappear into, and with Killing Sadie, it was no surprise that I read it over two sleepless nights, totally consumed. Liz is Sadie Cooper’s best friend. Ever since Liz moved to town, they’ve been inseparable. Liz became the Cooper family’s third daughter almost, much to Sadie’s twin’s chagrin. Jayne loathes Liz. Not that she wants to be Sadie’s best friend, either. They might be twins but they’re starkly different on so many levels that it’s no surprise they butt heads a lot. Like going to the famed McClain party. Sadie and Liz are forbidden to go by the Cooper’s parents, but somehow end up there anyway. Liz has always been a party girl, and where she goes, trouble follows—or at least that’s one story that’s being spun.

When Sadie is murdered by Mason, the school loner, who then gets killed himself by Sadie’s boyfriend, Ben, only three witnesses are alive to tell the tale of how it went down: Liz, Jayne and Ben. Liz is distraught that her best friend has been murdered. She only got there after the killings had went down, but she might know more than she’s letting on about the reasons why there is frostiness in the group. But how far back does she have to tell the cops—and which lies are worth not divulging? Jayne claims she held her dying sister after the murders and remains set on throwing blame Liz’s way for this entire ordeal, and every single thing before the killings. Meanwhile Ben, who’s own father had a similar police investigation years ago, was not the best boyfriend to Sadie. But is cheating his only crime? The group stand shakily on lies that are determined to break themselves—or one of the others—eventually. So when a renowned detective is brought in to dig deeper into the case and find out the real events of the night, the truth might not be as shocking as the lies growing thorns beneath where the true culprits sit.

Killing Sadie had this almost confessional, spotlighted way of pulling the reader into the past within the story, taking us along for the mystery as it unfolded. I have so much time for stories that flow in the way Sadie’s did, giving us this conflicting truth that leaves the reader able to unpick it as the narratives diverge into one. To tell the truth, I had suspected the true murderer, but not the reasons—and definitely not the actual events of the night, either. Rachel really knows how to curate suspense and the bittersweet teen experiences through the lens of differing upbringings. None of the characters are perfect—and they’re not supposed to be—and I really did love Liz. She was a hurricane and she was not always a great friend, but her heart was the one that came through the strongest. This story was such a triumph, an adrenaline-fueled ride that commands your attention from the get-go. I cannot wait to read more from Rachel, and I know this book is going to be devoured by so many thriller lovers this late-summer.