Caller Unknown by Gillian McAllister was a decent read overall. The story follows Simone as she flies to the US to meet her daughter Lucy for a camping trip. Before the women are able to depart, Lucy is kidnapped in the middle of the night and Simone is left following the kidnapper’s demands to get her daughter back. This book explored the lengths a mother is willing to go for her child.

I enjoyed this read for the most part. The twists and turns were entertaining and the character development was good. That being said, the story did drag in places. Simone’s internal dialogue was extremely repetitive making me wonder if I had gone backwards by accident. Constant rumination is probably natural in real life situations such as this, but in terms of the story, it just didn’t drive the plot along for me. Additionally, her recounting of recipes and thoughts of working in her restaurant back in England were irrelevant to the story and left me bored. The ending also felt abrupt with little explanation on the actual resolution.

Thank you NetGalley and William Morrow for the eARC in exchange for my honest opinion.

Meh. This book started good and failed to hold my interest as it went on. My first book by this author ✍️

Caller Unknown is one of those thrillers that grabs you right from the first page with its terrifying premise: Simone wakes up in a desert cabin to find her daughter Lucy gone and a phone demanding she comply if she ever wants to see her again. What follows is a messy, emotionally raw sprint across the desert, full of moral gray areas—Simone is fiercely likable, but also frustrating, making decisions you want to yell at. The tension bounces between heart‑wrenching moments (mother’s love, guilt, desperation) and the kind of plot twists you don’t see coming, though some parts drag a little in the middle and the ending wraps up a bit neater than I’d hoped. Still, it’s a fast‑read, emotionally intense, and asks big questions: how far will you go when everything feels like it’s on the line?

Thank you to NetGalley and the publisher for the ARC in exchange for an honest review.

McAllister has a real gift for creating tension and suspense—especially in the opening chapters. That kept me hooked early on. Unfortunately, the story didn’t quite live up to its strong start. The plot felt predictable, and the twist wasn’t particularly surprising. With so much potential, I found myself wishing it had pushed further.

I also found the heavy British nationalism distracting and unrelatable at times, which pulled me out of the story.

I’ve read and enjoyed other books by this author, but this one didn’t stand out for me. Still, readers who enjoy tightly wound openings and atmospheric suspense may get more from it than I did.

I don't think I'm a Gillian McAllister fan. Or at least not her most recent books.

Caller Unknown was "front loaded" with "action" and then slow afterward. Seemingly, all logic left the building, and there really was no exploration into the why of the lack of logic.

“So if you’re into thrillers with creepy phone calls, mysterious secrets, and that constant ‘who can you trust?’ feeling—Caller Unknown is definitely worth picking up. I’d give it about 3.5 star rating. Fans of Lisa Jewell or Riley Sager will totally vibe with this one.” Excellent book 🤗

This story had a lot of thought provoking moments. I'm not sure what I would do in her shoes. Beyond that it kept you wondering what was going on. I had no clue she was gonna do what she did.

This book was so good I binged it in one setting! I thought I had it figured out, but I didn't have a clue!

Simone flies to the U.S. to go camping with her daughter, Lucy. This is the longest they've ever been apart so she's really happy about spending time with her. They spend the night in a cabin before embarking on their adventure, but the next morning Lucy is gone. Simone calls her husband who drops everything to be with her, but she decides not to go to the police. What proceeds are a series of nail biting, dangerous escapades, and questioning how far will a parent go for their child?

I highly recommend picking this book up, but be prepared to lose some sleep because you won't want to put it down.

Thanks to the author, publisher, and NetGalley for an ARC of this book.

Thanks to NetGalley and William Morrow for this free copy of "Caller Unknown."

Every Gillian McAllister thriller is so different from the one before it, and while I'm furiously turning pages to see what happens, I'm also quietly shaking my head asking myself how they do it? Keep producing such gripping, compelling, (and entertaining) stories that are so emotionally and action(ly) layered.

There's usually a twist with the protagonists (Simone and her daughter Lucy) that you don't expect. And the situations are never quiet what they seem (Lucy's kidnapping). But you're cheering breathlessly for them.

So what would you do to save your child? It's every mother's nightmare.

Just okay. The beginning I was really invested in, but the middle was super slow for me then it picked up at the end.

I enjoyed this! I wasn't a huge fan of the main character's daughter, and "twist" didn't really do it for me, but overall was a good, standard popcorn mystery.

Thank you to NetGalley and William Morrow for sending me this book!

Caller Unknown had the potential to be a great thriller, but ultimately fell short for me. The unnecessary details and the constant switching between the past and present made it hard to follow. The story didn't feel realistic, and I found none of the characters likable. I’m giving it an extra star because I was intrigued enough to finish the book.

Thank you to Netgalley and William Morrow for the ARC. All opinions are my own.

This is my first book by Gillian McAllister and it was such a great read. What an incredible psychological thriller. Great character development and story telling. I enjoyed the suspense and the ending was unexpected. Thank you NetGalley for the ARC and I’ll absolutely be reading more from this author in the future.

Caller Unknown by Gillian McAllister is a tense, emotionally charged thriller that taps into every parent’s worst fear and pushes the boundaries of how far a mother will go to protect her child. The premise is gripping, and McAllister does a strong job weaving moral dilemmas into Simone’s harrowing journey through the Texas desert. That said, I found much of the inner dialogue and narration repetitive, which slowed the pace and made it feel like the real action didn’t kick off until nearly halfway through the book. While there were twists along the way, they didn’t quite land as mind-blowing for me, and I was left wondering if the emphasis on a traditional, heteronormative family structure was intended to overshadow other possibilities of what “family” means. Still, McAllister’s ability to craft tension and compassion in equal measure is evident, and readers who enjoy character-driven moral thrillers will likely find this a worthwhile read.

This was a first read for me by this author and I really enjoyed it. I requested it based solely off of the description and it didn’t let me down. I thought I had this book figured out and I was so far off haha! I think the writing was good, plot was good and the twit was amazing. I would absolutely recommend this book to my friends and anyone else who likes a good psychological thriller.

I was excited for Caller Unknown by Gillian McAllister after loving her last book, but this one didn’t stick with me as much. There were some strong moments and interesting ideas, but the suspense wrapped too early and was replaced with heavy backstory that didn’t feel essential. The ending also lacked a clean resolution, especially around the motive. Still, I appreciate her ambition with the premise. Thanks to William Morrow for the ARC.

This was my first book written by Gillian McAllister. I watched an instagram video of her discussing the premise and I could not wait to get my hands on this ARC. Unfortunately this was a miss for me. The pacing was incredibly slow with very little moving the plot forward. It seemed like the book wanted to be fast paced and suspenseful, but nothing was happening to get us there. By the time the ending was revealed it was a little deflated. I almost feel like this would have made a better movie than a book. Thank you to NetGalley and William Morrow for the ARC in exchange for my honest review.

God. I just cannot get enough of Gillian McAllister. Reading her novels is truly one of the highlights of my year, every year. I am so appreciative I was able to read CALLER UNKNOWN because WOW. I could not get enough. As always, McAllister snatches your attention right from the jump and had me itching to pick up my kindle at any moment I could, even if that only meant reading a couple pages.

My favorite part of this book, much like her others, is how much emotion lies within the pages. Her books are never just about the suspense and the thrill - they truly are about the deep emotions the character is feeling. While I am not a mom, reading this book made me feel like it was MY daughter I was fighting to get back. I believe parents everywhere, especially mothers, will appreciate this book extra because of the strong focus on motherhood.

And as per usual, the twist had me GASPING. Gillian McAllister is such a gift to the literary world and I am honored to read every word she writes.

4.75 stars (only because I honestly wanted more to read lol)

I just wrapped up Caller Unknown by Gillian McAllister, and I have to say, it kept me hooked for the most part. The premise is really intriguing, and there are plenty of tense moments that made me want to keep reading. That said, a few parts felt a little predictable, and I wished some characters had more depth. Still, the twists and emotional beats hit in the right places. If you like psychological thrillers that move quickly and keep you guessing, this one’s definitely worth a read.

3.75-4 stars. This is my fourth Gillian McAllister book, and possibly my least favorite, but it's not bad. I found the underlying premise/set up a bit silly and not believable, and I thought it was going to follow a predictable route. But like in McAllister's other books, she did surprise me some. One of my hunches did prove correct, and this book was a little slower at times, but overall, would still recommend.

Thank you to NetGalley and William Morrow for providing me with an advance reader's copy in exchange for an honest review.

Publishes May 5, 2026.