Thank you #Netgalley for the advanced copies from one of my favorite authors! In this suspenseful read, we follow the bond between a mother and daugther. The duo had planned to travel and connect for a camping trip, but a kidnapping takes place less than 24hrs of them arriving to their location. The story shows how far a mother would go to protect her child, at times even going against her husbands wishes. Who should she listen to? Should she call the police? Listen to her husband? The outcome of her decisions changes the path of their lives and takes them on a wild adventure and life of hiding. Who can they trust?

Great book. Lots of twists. Thank you for the ARC copy. Really enjoyed this one because it was suspenseful and really kept me wondering and suspicious of what would happen next

Thank you to NetGalley and William Morrow for the advanced copy in exchange for my honest review.

4⭐️
This one pulled me in right away—fast-paced, twisty, and with way more emotional depth than I expected. Perfect if you like thrillers that keep you guessing while also digging into those messy moral questions.
The tension never really lets up; I kept telling myself “just one more chapter” and then couldn’t stop.
The moral dilemmas land hard. How far would you go for someone you love? McAllister doesn’t shy away from that.
And the twist—no spoilers here, but it changes how you see everything that came before.
A few moments felt a little far-fetched, and the pacing slowed down in the middle before the ending kicked things back up again.
Overall, though, it was addictive and tense—and I flew through it.

Um. Let me catch my breath for a minute. I don't think I breathed for the entire length of this book! 

First of all, I need to apologize to my kids, because I am not this mom. I would call the police in a hot second if they were kidnapped. (I'm still not convinced that wouldn't have been a good call in this situation!) Following along on Simone's journey was almost too much for me, but I couldn't rip myself away. I haven't been this immersed in a book for awhile. I just couldn't figure out what would happen - every chapter seemed to dig the hole Simone and Lucy were in deeper. You absolutely need to read it. I'm just sorry I couldn't stop myself from diving in 7 months early, so it's going to be so long before I can discuss what happened!

At first I was a little unsure about it, as it seemed a little slow but boy was I wrong. Not only was I completely invested I related whole heartedly to the connection btw a mother and their child. One thing really hit home, that you never know the last you hold your child will be the last time.

Honestly… this one didn’t do it for me.

The premise had me hooked, a mother and daughter on vacation, daughter goes missing, and the kidnapper doesn’t want money, but something way darker. I was ready for, fast-paced, twisty.... darker. But after a strong start, it just kind of lost steam for me.

Simone (the mom) makes a lot of choices that don't feel believable, even with her daughter’s life on the line. I was more frustrated than tense, and the middle dragged with a lot of repetition and not a lot actually happening. The emotional angle is there, but the thriller part just didn’t hit.

I wanted more twists, more urgency. The ending was fine, but didn’t really stick with me. It’s not a bad book, just not what I was hoping for.

Thank you to NetGalley and William Morrow for this ARC!

⭐️⭐️⭐️💫 (3.5 stars)
Like other books I’ve read by Gillian McAllister, this one took me a while to warm up to. I even considered setting it aside at one point, but something always pulled me back in and kept me curious about how it would end. Unknown Caller is definitely a slow burn. I thought I had it figured out pretty early on, but I was wrong—and I’m glad I stuck with it to see the truth revealed.

It wasn’t as twisty or mind-bending as Wrong Place, Wrong Time, but it was still worth the read. The loose ends were tied up neatly, and while I didn’t completely love the resolution, it did leave me without lingering questions. Overall, a solid read with a satisfying payoff, even if it took some patience to get there

This isn't your typical kidnapping thriller. When Simone receives that devastating phone call and learns her daughter Lucy has been taken, the kidnappers don't want money—they want her to do "the unthinkable." This moral complexity becomes the novel's driving force, pushing Simone into increasingly impossible situations where every choice seems wrong, yet she must choose anyway.

What struck me most was McAllister's nuanced examination of how mothers and fathers love differently. The author doesn't shy away from the controversial assertion that "women love their children more than men," but then complicates it beautifully with the observation that "maybe we love her differently" and that children need both kinds of love—"different—but together, they are potent." This isn't about one parent loving more than the other, but about the unique ways maternal and paternal love manifest.

The author succeeds in crafting a thriller that forces readers to confront an uncomfortable question: How far would you go to save your child? And perhaps more unsettling—would you go further than your spouse? The result is a heart-pounding journey through the Texas desert that entertains while genuinely challenging readers to examine their own moral boundaries and the complex nature of parental love.

The twists that come in the final act genuinely surprised me, and the finale feels genuinely satisfying, bringing together all the moral threads McAllister has been weaving throughout. While the premise may stretch believability at times, the emotional truth at the story's core more than compensates for any logical leaps. This is a thriller that will stay with you long after you've turned the final page.

A big thank you to William Morrow and NetGalley for providing an advanced reader copy in exchange for an honest review.

Thanks for the opportunity to read this arc.
This book grabbed me from the start and I’m sure if I had worn my Apple Watch my heart rate would have alerted me from time to time.

I never pass up a Gillian McAllister book so I was thrilled to get the opportunity from NetGalley to scoop this one up. True to form, it was a thrill ride with twists that gave me whiplash, It’s full of tense moments and immense emotions as a moral dilemma is at play throughout. You won’t want to miss this one! RECOMMENDED

Gillian McAllister’s Caller Unknown is a tense, high-stakes thriller that starts with every parent’s worst nightmare and spirals into a morally complex journey through the dusty backroads of Texas. It’s gripping in premise, packed with potential, and has a few standout moments of genuine suspense—but ultimately, the book didn’t fully land for me, primarily due to pacing issues and difficulty connecting with the characters.
The story follows Simone, a devoted British mother on holiday with her daughter Lucy before she heads off to university. But the trip takes a terrifying turn when Lucy vanishes, and a phone left in her place begins ringing. A ransom call follows—not for money, but for something far more sinister. From that moment on, Simone is thrust into a desperate quest across unfamiliar terrain, making impossible choices in order to save her daughter.
McAllister does a great job building tension in the first act. The setup is chilling, and the central question—what would you be willing to do for your child?—is explored in some interesting and uncomfortable ways. There are some clever twists and turns that kept me turning the pages, especially as the true nature of the kidnapper's demands becomes clear.
However, I struggled with the pacing. After the strong start, the middle of the novel dragged at times, and the momentum occasionally fizzled when it should have been ramping up. The plot gets tangled in its own logistics, and rather than heightening the suspense, it sometimes slowed the narrative down.
I also found it hard to fully invest in the characters. Simone is believable as a mother desperate to do anything to protect her daughter, but I never quite felt emotionally connected to her or Lucy. Their bond, while central to the story, didn’t leap off the page in the way I hoped it would.
That said, Caller Unknown has its strengths. The desert setting is evocative, the moral dilemmas are well-played, and McAllister’s writing is as sharp and readable as ever. If you're a fan of thrillers that test the limits of familial loyalty and push characters into ethically gray territory, there’s plenty here to chew on.
Bottom line: Caller Unknown is a solid thriller with a compelling premise, but uneven pacing and emotional distance kept it from being a standout for me. Worth a read, especially if you enjoy morally-driven suspense—but maybe not McAllister’s best.

Caller Unknown started strong and I was excited to dive in after Gillian McAllister's other books. The story begins with Simone, Damien and Lucy, residents of the UK. Lucy, their daughter has traveled to Texas for the summer and Simone has been counting down the days until she gets to be reunited with Lucy in Texas. One morning, Simone wakes up and Lucy is missing. She is frantic, but then hears a ringing coming from a burner phone left behind with instructions how to get her daughter back. Her husband wants her to contact authorities, but Simone takes matters into her own hands. At first, I thought this would add more to the plot, but the further it went, I found myself not rooting for either of them by the end. I wanted to love this one as much as her other books, but unfortunately, it didn't live up to her previous novels. 3.5 stars

This one does live up to its name as a thriller, not the best I've ever read but also not the worst. The action was consistent, but even so I found myself bored with the story sometimes. The big twist was certainly a surprise I did not see coming, but it is also so unrealistic that it could actually happen that its no wonder I didn't connect the dots. The main characters overbearing relationship with her daughter was definitely distracting at times from the story - it seemed very unnecessary.

Thank you to Netgalley for the advanced copy!

I really enjoy Gillian McAllister's writing. It's perfectly pondering and exquisitely British. Her books always make me want a thick sweater and a steaming cup of tea. Her content is not cozy, but her words are if that makes any sense at all.
Caller Unknown starts really strong and I was quickly captured by the story. However, like McAllister's previous novels, the middle REALLY drags, and I think this one most of all. I stuck with it because I really wanted to know what would happen; but I could have done with out the ramblings through hundred of pages of mother/daughter relationships.
I liked and I disliked the end. I didn't see the twist coming, but once it came, it was time to end the book. The last three chapters after the epilogue (yes, I said AFTER the epilogue) were totally unnecessary.
Ther verdict? An entertaining book, but there are better thrillers out there!

I have read several of Gillian McAllister's books and have really enjoyed them. However, this one fell short for me. There is so much build up and anticipation of Simone finding Lucy, that the decision for her to take all the blame to dissolve Lucy's involvement completely was inevitable. I also felt the resolution was a quite quick and easy. There was no hint or even talk of Lucy searching for the kidnapper/kidnapper's daughter. It just felt a little to easy of a "clean-up" to me.

I also get that this was an "uncorrected e-proof" copy, but it was driving my crazy that the proper form of kidnapping/kidnappers/kidnapped/kidnap was hardly used. I think less than 5 times it was correct. When that is what your story revolves around, it should be right.

On a positive note, This is a great story of a mother's love and what she would do to save her child. Contrary to popular belief, a mother's love is completely different than a father's; not better, just different and more powerful. Though, don't get me started on this husband/father, as well as Lucy being spoiled and acting entitled!

Though, this book wasn't a "wow" for me, I will always be a fan of McAllister's.

Caller Unknown is a perfect title for this book. Gillian McAllister has written another thriller. Although it wasn’t a on the edge of your seat story, it was entertaining. Simone and Lucy’s mother/daughter trip takes a turn when Lucy is kidnapped. Simone was a likeable character and would do anything for her daughter’s safe return even bring drugs across the Mexican border.

Unknown Caller

Simone isn’t just having a bad day, she’s having a monumental shitty day. While visiting her daughter in Texas, Simone is forced to carry out multiple steps for the chance at ever seeing her daughter again. What started as a holiday in the US turns into a living nightmare, forcing Simone to not only rescue her daughter but also solve the crime itself. But who’s going to believe someone with zero evidence?

This book had me all over the place but really came down to a Who Dunnit without any suspects. How do you solve a crime without anyone to investigate? And what’ll happen if MC Simone can’t figure it out before it’s too late?? I re-read chapter 66 three times before it clicked for me. This was the furthest possible option in my mind but also makes sense without reaching too far! Definitely an enjoyable and memorable read! Thank you NetGalley and William Morrow for the ARC!

Thank you to NetGallery and William Morrow for an ARC of this book!

This book was a bit too unbelievable for me. While I’m okay with suspending some realism for a thriller to get the “wow” factor of twists, this book went a little too far out there for me with how the main characters handled situations and some of the scenarios they were in (like the desert scene).

I also wasn’t a huge fan of the mother/daughter dynamic in this book, which at times seemed a little weird. I understand wanting to do anything for your child, but some interactions felt off.

There were some good twists, and it was easy to read! It unfortunately just didn’t have what I was wanting based on the premise.

How far would a mother go to save her child?

Wow!! This is my first Gillian McAllister novel and it did not disappoint. Definitely not my last.

The conflict (kidnapping) began so quickly and I loved it! I thought I figured out what was going on but Gillian proved me wrong every single time. I was in the edge of my seat for most of it.

Another this is everyone is suspicious, so I could never trust my gut instinct after the first wrong guess. This was planned so well. The kidnapper was an evil mastermind.

Finding out who the “kidnapper” POV was SHOCKED me to my core. I was not expecting that insane twist.

Only two issues, but they are on me not the author:
1. The type of quotations marks used. I had a hard time with it in the beginning, and it took me a while to catch on.
2. Also had a hard time with the British slang. Used a lot of google LOL

otherwise, this was such a great thriller!! Really recommend!

A mother and daughter take a vacation to Texas from the UK to spend time together before Lucy leaves for university. But the trip quickly turns into a nightmare when Simone wakes to find her daughter missing and a cell phone left behind with a ransom demand and strict instructions: don't call the police. From there, everything spirals downhill with devastating consequences.

My biggest issue with this book was its predictability-the only real surprise came at the very end, which saved it from a lower rating. Most of the characters felt entitled (with the exception of the poor husband), and while I appreciated the fresh twist on a ransom story, none of it felt real.

Thank you to NetGalley and William Morrow publishing for my
ARC copy and my honest review.

Expected Publishing date: May 5, 2026