The Stepsister's Secret

by Karen King

She’s family now. But can I trust her?

When my stepsister Alison moves in to look after my mother, everyone in my family is grateful. Alison’s a nurse, and she says she just wants to help. But I don’t trust her.

Years ago, when Alison and I were the same age as my own son Isaac, I made a terrible mistake that tore Alison’s world apart. I hoped she didn’t realise, but the look in her icy blue eyes tells she knows exactly what I did.

I’m certain she’s responsible for my mother getting weaker. I don’t like the way she’s pushing me out, isolating me… and getting way too close to my husband, Nick.

I’m watching her. And I’ll do anything to keep my family safe. But I have no idea just how much danger we’re in…

A totally unputdownable, twisty story of family secrets that have deadly consequences. Perfect for fans of Shari Lapena, Freida McFadden, and Daniel Hurst.

What readers are saying about The Stepsister's Secret:

‘Wow!… utterly GRIPPING! 👌👌👌… drew me in from the very beginning… a rating of a whopping ⭐10! ⭐. Deffo a MUST-READ… I loved this book! I couldn't put it down.’ NetGalley reviewer, ⭐⭐⭐⭐⭐

‘I was hooked from the first page! This book had it all. Suspense, drama, family tension, paranoia it was all bursting out the pages. When I went to bed I was dreaming about it… I screamed at a bit! … Highly highly recommend!’ NetGalley reviewer, ⭐⭐⭐⭐⭐

‘Blown away… I could not turn the pages fast enough.’ Goodreads reviewer, ⭐⭐⭐⭐⭐

‘A brilliant and gripping read which I finished in one sitting.’ Goodreads reviewer, ⭐⭐⭐⭐⭐

‘Had me hooked from the first chapter!… I highly recommend!’ Goodreads reviewer, ⭐⭐⭐⭐

‘Such an addictive twisty thriller… hooked me from the start… bingeable.’ Goodreads reviewer, ⭐⭐⭐

Genres: Audiobook

332 pages, Kindle Edition

Expected publication February 16, 2026

About the author

Karen King is an Amazon international bestselling author of psychological suspense and women's fiction.

Her 7th psychological suspense novel, Don't Trust Him, was published on 3 April 2025 by Bookouture and her 'golden years' novel, The Runaway Wives, was published by Boldwood on 24th March 2025. This was her 12th woman's fiction novel.

Karen has also had 120 children’s books, two young adult novels, and several short stories for women’s magazines published. Her early writing career was spent working on various teenage and children's magazines.

Her suspense novels The Mother In Law, The Perfect Stepmother and The Stranger in my Bed and her romantic novel The Cornish Hotel by the Sea all became International Amazon bestsellers.

Reviews

[Bridget Sadenwater · Rating 5 out of 5]

The Stepsister’s Secret is a twisty, addictive thriller that I thoroughly enjoyed. Lizzie and Nick appear to have a happy, settled life with their children, and when Lizzie’s widowed mother becomes engaged to George, everything seems positive—he appears to be a perfect match for her. But once George’s children are introduced, the story takes a darker turn as connections from the past begin to surface.

What really stood out to me was how the clues were revealed slowly and deliberately. Each piece of information builds on the last, keeping the tension high, and I did not see the final twist coming. The pacing and suspense made this a hard book to put down.

I don’t want to give anything away, but if you’re a fan of Freida McFadden-style psychological thrillers, this is absolutely a must-read. A strong 4.5 stars, rounded up to 5.

[Kim McFall · Rating 5 out of 5]

I loved this audiobook so much!! It was narrated by my favorite narrator and there are multiple POV’s!

The storyline started out so strong and grabbed my attention from the very beginning. Full of suspense, twists and shocking revelations with each new chapter.

Everyone has a secret, you don’t know who to believe or trust, and it keeps you guessing until the very end.

This is the perfect psychological thriller full of buried secrets, sinister revenge, psychological manipulation & gripping suspense.

⭐️⭐️⭐️⭐️⭐️

[KKEC Reads · Rating 4 out of 5]

The Stepsister’s Secret by Karen King
Holy chaos! This was quite the ride from start to finish. Secrets, twists, turns, and plots for revenge. This took everything, tossed it in the mix, and my goodness… did it ever explode.

I enjoyed how this story was told. Alternating narrators, the timelines, and the mysterious person out for revenge. It was all quite clever. While I guessed who the mysterious person was, there were so many elements I didn’t see coming, and that left my jaw on the floor.

I was drawn into this story, and wanted to fight right beside Lizzie as she tried to protect her beloved mum. To know something isn’t right, but have people insinuating that you’re crazy- I can’t imagine how horribly isolating that had to be.

This had all the highs and lows you want from a well-written thriller. Strong characters, secrets, and someone wants revenge. Brilliantly written, flawlessly delivered, and impossible to put down.

Publication date: February 16, 2026
Publisher: Bookouture

[Kristen · Rating 5 out of 5]

Thank you to NetGalley and the publisher for a copy of this audiobook in exchange for an honest review.

This book was so gripping! I loved the multiple points of view, especially the few chapters from the culprit’s POV as it had me questions who was behind everything throughout the book. I enjoyed the way in which the book had the reader questioning Lizzy and her sanity throughout the whole book through her actions. I really enjoyed this book and did not want to put it down at all.

[Leah M · Rating 4 out of 5]

Thank you to NetGalley and Bookouture Audio for providing me with an ARC of this audiobook in exchange for an honest review.

Karen King is a new-to-me author, and I was looking forward to checking this one out. I wasn’t sure which way this would go for me, since it’s compared to books by Shari Lapena (love her writing) and Freida McFadden (not an author I read anymore since seeing her harmful and inaccurate mental health rep). I was hoping it would be as enjoyable as Lapena’s books are, even if it requires a little extra suspension of disbelief.

The story seemed pretty straightforward initially. Everyone seems to have secrets in this family, and I was thrilled about it. I love a suspense novel that is full of hidden secrets that are bound to come out at the worst possible time. There are multiple POV characters, including Alison, Lizzie, Nick, and Lizzie’s mother, and it seemed like a typical, predictable plot.

However, it becomes clear that in addition to keeping huge secrets, not all of these narrators are reliable. Lizzie in particular becomes an unreliable narrator when more about her is revealed. I didn’t love that her mental health becomes a plot point along with her being unreliable, but it was presented relatively decently. She struggles with anxiety throughout the book as well, and she doesn’t always reach for the most helpful coping techniques. One of the techniques was to wear something around her wrist that she can snap when feeling anxious, which is a harm reduction technique commonly used to stop self-harm. However, she does so unconsciously to the point where it causes physical damage to her wrist. When her loved ones see her wearing it, they become more overprotective—viewing it as a sign that her anxiety levels as high and they assume that they need to ‘protect’ her rather than being actively supportive. I mean, I don’t think that it is an intentional response, but family doesn’t always know how to support a person with mental health issues.

Along with nearly everyone in the story walking on eggshells in an effort to manage Lizzie’s anxiety, Alison infantilizes Lizzie’s mother and everyone in the family simply views it as providing care to her stepmother (except for Lizzie). It becomes clear that Alison’s nursing skills are a way of controlling her new stepmother—she decides who can visit, how long they can stay, and what she is capable of handling, furthering the idea that Alison might be doing something to harm her.

The audiobook is narrated by Imogen Church, who does a fantastic job of voicing multiple characters, tones, and even accents. It was a pleasure to listen to her, even if I wasn’t sure about the plot at first. Church makes the fast-paced chapters fly by, and it was an enjoyable experience.

For the first part of the book, things seemed entirely too predictable. There’s a strange connection between Lizzie and Alison, dating back to when they were very young, around the same age as her 7-year-old son. It was a simple mistake with huge consequences, and it changed the course of the life of everyone involved in the story. This is where Lizzie’s crippling anxiety began, and it was surprising to me that no one in her family noticed the drastic change in her and questioned what it was about. But it’s easy for me to say that as a trained mental health counselor, while loved ones do their best with the limited information and supportive skills that they have.

Initially, all of the evidence seem to point very clearly to Alison. Also, Alison doesn’t seem very mentally steady. She resorts to calling her new stepmother ‘Mum’ right away, and then cancels her return flight to Spain, offering to stay with her father and new mum so they can benefit from her training as a nurse. But something isn’t right—Lizzie’s mother has some worrying symptoms as she’s recovering from a fractured ankle. She’s tired all the time and has become especially weak, and has become completely dependent on Alison in the blink of an eye.

Overall, I found that I enjoyed the second half of the book a lot more than the first half. Whenever I read a mystery or suspense novel, I’ve learned that if everything points to one character, they’re usually the one person who isn’t involved at all. So I tried to stay open-minded, and really struggled with figuring out who the villain is. Most of the plot twists in the book were a complete surprise, so that every time I got to feeling like I knew what was going on, King would throw in a major twist that changed the entire direction of my thoughts. The plot twists were done so well, and each one altered the whole trajectory of the story along with my thoughts. Just be warned, this book is like popcorn—a little isn’t enough.

[Aisha Faisal · Rating 5 out of 5]

My thanks to Bookouture and NetGalley for providing me with an ARC of The Stepsister’s Secret. I really enjoyed this gripping, twisty read and appreciated the opportunity to read and review it early. I flew through The Stepsister’s Secret. This was one of those “I’ll read a few chapters” books that somehow turned into “oops, it’s finished”.

Lizzie seems to have a pretty settled life with her husband Nick and their kids, so when her widowed mum gets engaged, it should be a happy change… right? Yeah, no. Enter George and his adult children, especially Alison, Lizzie’s new stepsister, and the whole vibe shifts fast. There’s history here. Dark history. The kind Lizzie has spent her whole life trying to forget.

What I loved most was how slowly and deliberately everything unfolded. The author doesn’t rush the reveals; instead, the tension keeps tightening. Alison comes across as calm, capable, helpful… almost too perfect. And once Lizzie’s mum starts declining, and Alison steps in to “help,” the atmosphere turns properly claustrophobic. I was constantly questioning whether Lizzie was being paranoid because of her anxiety, or whether something genuinely sinister was going on.

The psychological side of this really worked for me. The guilt Lizzie carries from her childhood, the way old wounds resurface, and that constant feeling that no one quite believes her it all made the story feel so unsettling in the best way. I had my suspicions (obviously), but the book plays with that so well that even when you think you’ve got it figured out, you’re still not totally sure.

Nick deserves a quick shout-out because he was genuinely supportive and grounding a rare thing in domestic thrillers, honestly. His presence made the tension hit harder because there was actually something stable at risk.

By the time the final twist hit, I was fully invested, and yes, it still managed to surprise me. I was genuinely disappointed when it ended, which is always the biggest compliment. A brilliant and gripping read, which I finished in one sitting. Highly recommend.

Dark, twisty, and very addictive, this is a great pick if you enjoy Freida McFadden–style psychological thrillers where family secrets, buried guilt, and quiet revenge simmer just below the surface. Dark, gripping, and quietly unnerving, The Stepsister’s Secret is the kind of book that makes you say “just one more chapter” until suddenly you’re at the end and wishing there was more.

[Barbara Schultz · Rating 3 out of 5]

Title: The Stepsister’s Secret
Author: Karen King
Format: 🎧
Narrator: Imogene Church
Publisher: Bookouture Audio
Genre: Domestic Thriller
Pub Date: February 16, 2026
My Rating: 3.3 Stars
Pages 322

Lizzie and Nick have two young children Grace and Isaac and they are all pleased that Lizzie’s mother Judith who has been a widow for years is getting married to a man named George. The children are excited about getting a grandfather as Nick’s father also died.
However at the wedding when they meet George’s children. Lizzie is surprised when she sees new stepsister, Alison. She remembers her from when they were children and Alison’s mother died from a reaction due to her peanut allergy. Lizzie has believed she was responsible as she had a peanut butter sandwich for lunch and threw the remainder of into Alison’s lunch bag.
Present day Judith fell and needs assistance; Alison is a nurse and volunteers. Lizzie fears her mother is in danger as Alison may want to ‘pay back’ Lizzie for her responsibility in her mother’s death.

Okay Lizzie is a bit over the top with her worries but guilt is a terrible burden and in this case has not gone away.

Things do get bizarre as Lizzie loses all sense of reason.
I kept at it as I was curious. The ending was satisfying.

The Girl Next Door was my first Karen King thriller which I really enjoyed and have been looking forward to reading another of her thrillers.
I guess my expectations were too high as this wasn’t the Wow read I was looking forward to reading. But I will definitely read another of Ms. King’s thrillers..

Want to thank Bookouture Audio for this audiobook.
Publishing Release Date scheduled for February 16,, 2026.

[Leanne · Rating 4 out of 5]

The Stepsister’s Secret is a gripping, quietly unnerving domestic thriller that pulls you straight into a world where old wounds never quite heal and family ties can be as dangerous as they are binding. From the moment Alison moves back into the narrator’s life, the tension begins to coil — subtle at first, then tightening with every chapter.

The dynamic between the two women is wonderfully layered. On the surface, Alison is the perfect helper: a nurse, a dutiful daughter‑figure, someone the whole family is grateful for. But beneath that polished exterior lies a shared history marked by a single devastating mistake — one the narrator has spent years trying to bury. The author captures that uneasy blend of guilt, suspicion, and unspoken resentment with real finesse.
As the mother’s health declines and Alison’s presence becomes increasingly suffocating, the atmosphere shifts into something deliciously claustrophobic. The narrator’s growing paranoia — is Alison isolating her, undermining her, getting too close to her husband? — is handled so well that you’re constantly questioning what’s real and what’s fear talking. It’s exactly the kind of psychological tension that keeps you reading “just one more chapter.”

The story unfolds with sharp pacing, clever twists, and a steady drip of revelations that make you reassess everything you thought you knew. By the time the danger becomes undeniable, the sense of dread is wonderfully intense.

Dark, twisty, and utterly addictive, The Stepsister’s Secret is a perfect pick for fans of Shari Lapena, Freida McFadden, and Daniel Hurst — a domestic thriller where every glance, every silence, and every secret feels like it could be the one that breaks everything apart.

My thanks to Karen King, the publisher and netgalley for the ARC

[Els · Rating 5 out of 5]

When, as a child, you witness a tragic event, you carry it with you for years—especially when you come to believe that you were responsible for the tragedy.

You were a child. Yes, that’s true, and deep down you know it was never your intention and that it was an innocent mistake. But that doesn’t change the outcome.

Years later, you are confronted with the event all over again when you come face to face with one of the key people involved back then. You fear the worst, yet you still hope you weren’t recognized. Sadly, you were—and now you’re convinced that revenge is lurking just around the corner.

You want to intervene, but you’re on your own. No one believes what you’re saying and they think you’ve slipped back into your old habits…

My focus immediately fell on the most obvious person. Of course, that would be too good to be true, and more often than not this is a smokescreen carefully set up by the author. But perhaps this time the obvious choice is the right one—and maybe it’s precisely that doubt that’s being planted.

Who knows? I certainly won’t say, because I don’t want to deprive anyone of a fantastic book by giving too much away. 🙂

I found the book smoothly written and suspenseful. I was genuinely disappointed when it ended, which tells you everything—you only feel that way when a book is really good.

Sometimes people do things for you, or for others, with the very best intentions—but sometimes they’re after something entirely different…

For me, this book is definitely a recommendation and well worth five stars.

Thank you

[Cassia · Rating 4 out of 5]

3.5 stars rounded up for goodreads!

The Step Sister’s Secret is perfect for readers who love fast, twisty domestic thrillers—especially fans of Frieda McFadden. This is a story that wastes no time getting started and keeps the pace brisk from the very first chapter. The twists come quickly, and just when you think you’ve figured it out, another turn pulls the rug out from under you.

Karen King’s writing is clean and straightforward, which works well for this kind of book. It isn’t fussy or overly descriptive—just tightly focused on momentum and tension. I flew through it, making this a great palate cleanser if you’re in the mood for an easy, popcorn thriller that keeps the pages turning.

My one critique is the ending, which wrapped up a little too neatly for my personal taste. I tend to prefer darker or more messy endings, and this leaned more toward a tidy resolution. That said, if you enjoy thrillers with clear closure, this may actually be a plus.

I listened to the audiobook and want to give a special shout-out to Imogen Church, who is always a standout narrator. She did an excellent job handling the multiple POVs and brought distinct voices and tension to each perspective.

Thank you to NetGalley and the publisher for the advance listening copy. Overall, this was a fun, addictive read/listen that’s ideal for thriller fans looking for something quick and engaging.

[Pages & rituals · Rating 4 out of 5]

ARC Review

When Lizzie’s mother decides to marry George, Lizzie is forced into a new family dynamic she never asked for. When she meets her new stepsister, Alison, she quickly realizes that Alison is not just part of her future but is tied to a very dark secret from Lizzie’s past, a secret they both share.

As the story unfolds, one question lingers. Is Alison here for revenge, or can she be trusted?

This book is packed with secrets, tension, and that constant uneasy feeling that something is not quite right. If you enjoy Freida McFadden–style thrillers, I think you will really like this one. I had my suspicions about what was going on, but even so, the final reveal still managed to shock me.

Nick was easily my favorite character. He was such a devoted husband and genuinely supportive of Lizzie throughout everything. His presence added a sense of stability in a story full of uncertainty.

Overall, this was a very enjoyable read. It was gripping, twisty, and hard to put down. I definitely recommend it if you are in the mood for a suspenseful domestic thriller full of secrets and surprises.

[Jennifer TW · Rating 5 out of 5]

A woman riddled with anxiety. Her mother, widowed and set to remarry. A new stepsister who seems intent on embedding herself into their lives.
Lizzie, a mother of two is married to Nick. She lost her father who died in a work accident when she was young and Nick delivered the sad news. Lizzie suffers with chronic anxiety triggered by an incident in her childhood. A tragedy she has convinced herself she is responsible for. Her beloved widowed Mum, Judith, meets and marries George, himself a widow, and soon Lizzie finds herself with a new extended family. But George and his adult children seem intent on embedding themselves very quickly and when Judith takes a funny turn, injuring herself in the process, new stepsister Alison volunteers herself to take care of Judith much to Lizzie’s dismay. But the thing is, Lizzie knows who Alison really is. And she’s worried that there are dark motives at play.
A brilliant and gripping read which i finished in one sitting. Highly recommend . Huge thanks to the author & publisher for an ARC in exchange for an honest review

[Curt Dunnam · Rating 4 out of 5]

“The Stepsister’s Secret” by Karen King is a twisty 4-star read! Lizzie is trying to live a peaceful, quiet life with her husband, Nick, and their two children. That all changes when her mother, Judith, meets George online and their whirlwind relationship quickly turns into marriage.

The story is told from three different points of view: Lizzie, Judith, and Nick. There is so much tension between these three characters, not to mention, as the title suggests, between Lizzie and her stepsister. The entire time I was reading, I had the same phrase repeating in my head: “You have a secret! You have a secret! Everybody has a secret!”

Some portions felt a bit repetitive, but it did not take away from my overall enjoyment. With so many secrets in play, there were plenty of twists to unravel, some more shocking than others. Overall, I really enjoyed this story and look forward to what the author writes next.

Thanks to Bookouture, Karen King, and NetGalley for providing me with the opportunity to read this ARC and share my honest review.

[Den · Rating 4 out of 5]

This is a great "just another chapter!" book. It never lets up. Intriguing information is trickled out with such regularity that you always want to know just a little more. I was riveted. Every single person starts looking guilty at different points in the book.

That said, I'm mostly a physical book reader and I only listen to audiobooks when I'm in the gym, so it takes me a while to finish an audiobook. This one I just gobbled up, I started listening to it whenever I could, even while I was doing other things. The narrator was fantastic at keeping tone with the multiple POVs.

I have to say though, the villain monologue at the end took me out of it a little bit. It even came with an evil laugh and at some points became like a Q&A portion ("But why did you do A?" "That's because reason B! mwahahah") I know most thrillers like these do the 'villain monologue' at the end, but I will never get used to it.

Would still absolutely recommend to anyone in the mood for an absolute page turner of a thriller.

[Ali O · Rating 5 out of 5]

The Stepsister’s Secret by Karen King
Narrated by Imogen Church
🌟🌟🌟🌟🌟
This is a very exciting and intense psychological/domestic thriller!! The twists and turns were non-stop through the entire book. I definitely was surprised and did not guess what was going to happen next.
There are secrets and lies and guilt galore!

Lizzy’s mom, Judith, is getting married years after her first husband passed away. What is supposed to be the best day, and best honeymoon, takes a sour turn. Judith has a fall after the wedding and Alison, steps in to help nurse her back to health. Alison is Lizzy’s new step sister and the chaos begins!

There is great character development and each character seems to play a big role. I really enjoyed the multiple POV as well!

Thank you to NetGalley for an audio arc of this exciting thriller!! This is my first read from this author and I’m excited to read more!
The narrator did an excellent job! I definitely recommend the listen!!

*This book comes out February 16th!*

[Angel **Book Junkie** · Rating 5 out of 5]

The Stepsister’s Secret by Karen King was an absolute blast, and the audiobook? Chef’s kiss.

This story was freaky, twisty, and completely unhinged in the best possible way. Just when I thought I had things figured out—nope. The ending rocked my world and caught me completely off guard. And that does not happen to me often. I was genuinely shocked, jaw-on-the-floor shocked.

I loved the characters and really enjoyed the dual POVs, which added so much tension and kept the story moving at a perfect pace. Every chapter made me want to keep listening “just one more minute”… which turned into hours.

The audiobook production itself was fantastic. The narration pulled me in immediately and elevated the suspense even more. This is one of those stories that absolutely shines in audio format.

Thank you to NetGalley, Bookouture Audio, and Karen King for the opportunity to listen to this audiobook in exchange for an honest review. This one delivered on every level—creepy, addictive, and wildly unpredictable. I’m still thinking about that ending.

[A Lane · Rating 4 out of 5]

The Stepsister's Secret is a gripping and chilling psychological suspense story that is unputdownable.

When Lizzy's mum remarries years after the death of Lizzy's father, they all have high hopes for a warm and fuzzy family unit. At first it seems to be coming to fruition, but soon things keep happening one right after another. Knowing she is carrying around a secret from her childhood, Lizzy begins to wonder if someone in her new family is out for revenge.

This was such an addictive twisty thriller that hooked me from the start. It was told through multiple perspectives, and the writing flowed seamlessly, making it bingeable. The ending took me by surprise, and was perfectly crafted. I always look forward to Karen King's new arrivals. This one did not disappoint.

Thanks to Netgalley and Bookouture for the advanced copy

[Lisa Gilbert · Rating 4 out of 5]

This is a fast-paced read that centers on past guilts and hidden agendas. There is a hidden layer of tension as the reader wades through what is perception and what is real.

When Lizzie was only 7 years old, she witnessed the death of a classmate’s mother during a field trip. Lizzie has always felt at fault because she had a peanut butter sandwich for lunch and this mother died from anaphylactic shock. Now, 25 years later, she finds out that her own mother just married the widower of the dead woman. Shortly after the wedding, bad things start happening, and Lizzie is convinced that someone is out for revenge. Or is it her crippling anxiety that has her thinking this?

Throughout the story there is a strong atmosphere of suspicion, and combined with the short chapters, it’s easy to binge read this chilling psychological thriller.

Thank you, NetGalley and Bookouture for the eARC.

[Othnielle_lit · Rating 4 out of 5]

This book seriously messed with my mind. At one point I was SO mad…

Can we talk about why main characters in thrillers are often so impulsive and make the most questionable decisions?? I was stressed the entire time!

Overall though, I really enjoyed this one. There were a few inconsistencies (imo), but they didn’t stop me from having a great reading experience. I couldn’t put the book down while reading, and I definitely couldn’t pause the audiobook when I was listening at work.

Every single main character annoyed me at some point for one reason or another, but honestly… I loved that. That constant feeling of not trusting anyone, never knowing who to believe, kept me fully hooked from beginning to end.

If you enjoy thrillers that play with your mind and keep you suspicious of everyone, this one will definitely keep you entertained.

[Becky Geller · Rating 4 out of 5]

⭐ 4 stars

Thank you to Bookouture and NetGalley for the ARC!

I really enjoyed The Step Sister’s Secret and found it to be an engaging psychological thriller. I stayed entertained from start to finish and liked how the story explored its characters through both present-day events and moments from the past.

The multiple POVs added depth and kept the pacing steady. While there were a few sections that felt slightly drawn out and I did figure out the twist before the reveal, it didn’t take away from my overall enjoyment.

Overall, this was a solid psychological thriller and one I would recommend to fans of domestic suspense. Definitely worth checking out when it releases on February 16, 2026!

[Booklovingolfer · Rating 3 out of 5]

I would like to thank NetGalley and Bookouture for the advance audiobook copy in exchange for an honest review.
The Stepsister’s Secret was a fast-paced, twisty read that kept me turning the pages. The short chapters and constant reveals made it easy to fly through, and I enjoyed not always knowing where the story was headed. Everyone had secrets, not just the stepsister!
That said, the repetition held it back for me. Certain points and emotions were revisited a bit too often, which slowed the momentum and made parts feel longer than necessary. I also figured out the ending pretty early in the book which does not happen very often for me. It was a bit too predictable.
I would recommend it to readers who enjoy quick psychological thrillers with plenty of twists.

[Britney Ireland · Rating 5 out of 5]

The Stepsister's Secret by Karen King
First I want to thank #NetGalley for the ARC read in return for my honest review.

I really enjoyed this read! I am giving it 4 stars.

Quick overview. Lizzies mother is marrying George after her father had passed away several years ago. Once introduced to George's daughter Lizzie is shocked to see someone from her past! But does George's daughter realize who Lizzie is? Lizzie isn't the only one with a secret. Can she keep the past from her husband Nick? Who else is hiding something?

So many twist and turns and I really enjoyed this book from start to finish. It had short chapters which I like.

I definitely recommend this read!

[Lindsay · Rating 5 out of 5]

So this is a dark story around a young mother who on her mothers wedding day finally meets her new step sister, the only problem is she already knows her and she is linked to a dark secret long buried which the woman has never recovered from. As she starts to fear for her own sanity and her mother’s health she starts to question everything around her including her husband. Is she really being punished for something this happened as a child or is she loosing her mind. This is a great read with a great finale so I won’t ruin it. Not to be missed!

[Tamara Hamilton · Rating 4 out of 5]

The StepSister's Secret is a topsy - turvy fast paced psychological thriller. I really enjoyed this one. It is filled with lies, secrets, family drama, paranoia and revenge.. You get to know the characters in present time and with glimpses into their past. Everyone seems to have secrets and feelings of unwarranted guilt. Karen King masterfully draws you in and keeps you interested. Just when you think you know the truth, You do not. Great book.

Thank you Netgalley and Bookouture for my ARC in exchange for my honest review. Highly recommend. Expected release date is February 16 2026

[Cin (cinsnextchapter) · Rating 5 out of 5]

The Stepsister’s Secret is a super twisty psychological thriller that completely pulled me in. I loved this book—it’s my first time reading Karen King, and it definitely won’t be my last! The tension is high right from the first chapter, and I could not put it down!

The short, gripping chapters made it way too easy to keep telling myself “just one more,” and before I knew it, I’d finished the whole book. This one ticks all the boxes for me. Totally binge-worthy and packed with unexpected turns. Five stars!

[Laken Lee · Rating 2 out of 5]

ugh... I'm an outlier here. I just did not enjoy this at all. I found it repetitive.
Maybe it was the main character or narrator? It was the narrator as the main character. It's in 3 povs and the narration of the other 2 weren't nearly as cringy.
Lizzie is whiny and annoying.
Anxiety is so real but I couldn't relate with how it was displayed in this character.
Very Freida McFadden vibes, which I am not a fan of, but if you are this is for you! Or maybe read it instead of listening

[Siobhan O · Rating 5 out of 5]

Karen, you have become one of my instant yes please Authors.

Are you after a fast pace audiobook that has multiple POV's, full of suspense, twists and shocking secrets... I mean I'm pretty certain each secret had a secret.

This is a great psychological thriller where it keeps you on your toes and leaves you wondering who you can and can't trust.

I'm adding the rest of your books onto my TBR!!

[JennaJustReading · Rating 4 out of 5]

This was one of the best, twistiest thrillers I've read in a long time. Usually I have the plot figured out almost from the first. "The Stepsister's Secret" has several mystery threads to follow and does a masterful job of getting the reader to doubt everyone at some point. If you want to be gaslit by a book in the best possible way - this is the one to do it!

I listened to the audio book and found the narration very good and clear. Thank you NetGalley and Bookouture Audio for the alc.

[Amber Rothermel · Rating 3 out of 5]

This was the run of the mill domestic thriller. To me, there was nothing that made it stand out or made it unique. Lots of lies & deceit, but nothing entirely twisty.

It did not surprise me who the culprit was because the narrator spoke in a low deep voice when it got to his POV. So, process of elimination.

Despite some of the drawbacks, I still was entertained as the story went on and felt engaged. I listened at 2x and the narrator did great other than reveal the bad guy.

[Arleigh Salerno · Rating 5 out of 5]

well... that was the opposite of the ending I was guessing at. pretty sure while listening to this audiobook at work that I kept telling it "she's doing it!"... I had only began to have an inkling of what the ending turned out to be. and it was NOT the person at the center of it that I thought it would be. I mean I definitely liked the ending and this audiobook really had me wondering... a nail biter.