Head Under Water

by Kiersten Modglin

Opal Sullivan has a plan:
- Move home to help her mother grieve the loss of her best friend
- Stay in her childhood home until she finds a place of her own
- Keep far, far away from Will Kendricks

Opal’s plan falls apart before she can unpack the first box.
- Too many questions still linger around Ruth’s death
- Her mom has already found her a new roommate
- The new roommate is Will

Growing up as neighbors with best friends for mothers, Opal has never been able to untangle her life from Will’s. He was the boy who teased her, the teenager she hated, and the man she never understood. And after one night they’ve kept buried all these years, they stopped speaking altogether.

Now they have no choice but to break their rules if they want the truth about Ruth’s death.

Because something isn’t right.
The town and life that once felt so safe now simmer with unease.

When tragedy strikes again, Opal knows time is running out. The deeper she digs, the more certain she becomes: whatever truths they uncover might be more devastating than all the lies.

Pulled together by grief and suspicion, the boy she once despised becomes something far more dangerous—someone she can’t quite trust, and yet can’t bring herself to let go of. Are they ready to face the past they’ve both tried to forget?

Will might be her downfall…
Or the thing that saves her from it.

Three-million-copy bestselling author Kiersten Modglin returns with a haunting blend of romantic suspense and psychological thriller. This high-angst and totally unpredictable enemies-to-lovers, forced proximity story is dripping with tension, yearning, and shocking secrets that will have you falling desperately in love and obsessively searching for answers with every turn of the page.

Genres: Audiobook

388 pages, Paperback

Published September 22, 2026

About the author

ABOUT KIERSTEN MODGLIN®:

Welcome to the KMod Squad—

The rooms change here.
The house stays the same.

KIERSTEN MODGLIN is a #1 bestselling author known for unique and unforgettable stories that explore the cobweb-filled corners of human nature. Her stories cross genre lines, inviting readers to follow her into psychological thrillers, domestic suspense, romantic thrillers, mysteries, and emotionally driven fiction. Each novel opens another doorway into the KMod Universe, where ordinary people and seemingly harmless decisions unleash blindsiding consequences.

A fiercely independent author, Kiersten has built her career around creative freedom, fearless storytelling, and a direct connection with the readers who have come along for the ride. Her books have sold over three million copies worldwide, been translated into multiple languages, and earned recognition including KDP Select All-Star, ThrillerFix’s Best Psychological Thriller Award, Suspense Magazine’s Best Book of 2021 Award, and multiple Silver Falchions.

From the darkest parts of the human mind to stories of resilience, love, and survival, Kiersten’s novels invite readers to explore an ever-expanding world where each story promises to be everything they hope for and nothing they expect. Her readers lovingly coined the name “KMod” early in her career, and it has grown into more than a nickname. It represents a storyteller whose curiosity leads her—and the readers who have joined her—through doors they never expected to open.

Make yourself at home here. Look around. Step into the next room. You never know what’s waiting for you.

Reviews

[GCR | Book Realm]

ALC provided by High Gravity Productions.

Head Under Water had some interesting moments, and one of my favorite parts was the three moms raising the kids together. I loved that whole family dynamic. The romance between Opal and Will was the center of the story.

The thriller side worked less for me. I figured out what was going on pretty early, and with such a small group of characters, the mystery wasn’t hard to narrow down. There was also one scene where the logic completely lost me, which made the reveal more frustrating than surprising.

Persephone Lee did an amazing job with the single narration. Her male and female voices were both strong, and her tone and delivery really helped with the tension. Even with the time jumps, the audio was easy to follow, and her performance added more to the suspense than the plot itself did for me.

Overall, I liked the romance and family side more than the mystery, but the narration was definitely a highlight.

I’d recommend this to readers who like romance-forward suspense, and strong single narration.

[Nina (ninjasbooks)]

1,5 hours in and I’m capitulating. I’m just too old for the ‘I hate you, but somehow I realize I was wrong’ trope.

[Laura Smith]

HEAD UNDER WATER BY THE LITTLE LEGEND THAT IS KIERSTEN MODGLIN
5 ✨ ✨ ✨ ✨ ✨s
I absolutely adored this book.
I loved the family dynamics and it was perfect.
The chemistry and romance between Opal and Will was just perfect.
This book cover is 🔥  love it.
Any fan of Hemlock will absolutely devour this story.
I highly recommend this book to every Romance Thriller lover ♥

[Emerald]

Mysterious, charming, and filled with tension, this romantic thriller buzzes with electrical chemistry.
Modglin expertly crafts a fresh and unique balance between angst, fear, and heartfelt moments like no other.
With scenes I'm STILL thinking about, this brilliant page-turner will have you in a chokehold from page one (guaranteed!) and leave your head spinning by the very end.
All the stars! My favourite read of the year.

[Casey Reads 🌸]

This was entertaining, but it was extremely predictable from very early on. I knew everything that was going to happen. I think it was because of the prologue which just made it too easy to guess everything next.

I still really enjoyed the first half of the book though and the chemistry love/hate relationship between the 2 main characters. However, I think it lost the magic in the 2nd half. To me, the writing got a little bit silly and I had already predicted everything, but I stuck it out until the end.

I would say this book is entertaining enough to read if you are bored, but it is not going to blow your mind at all. 3 stars for sure.

[Cody Moore]

Kiersten Modglin does it again, but Head Under Water completely caught me off guard in the best way possible!

Will is my new book crush! This is heavy on the romance end, but I promise you won’t even care what happens in the mystery, you just have to know what happens with Opal and Will first. Well, at least for me anyways! I’m not typically a romance girlie, but this enemies-to-lovers story is so worth the pick-up.

The forced proximity of them unexpectedly having to live together while trying to uncover the truth behind Ruth’s death creates an absolute pressure cooker of tension and yearning.

Narrator Persephone Lee brings every drop of suspense, history, and raw emotion to life so seamlessly. If you're looking for a romantic thriller with high angst, wild twists, and unforgettable chemistry, press play on this audiobook immediately!

[Kris Ream]

Phenomenal

I am such a fan of Kiersten and the twists and turns of her books. I read this book so quickly to see if my theory was correct!

[Jaimie]

3.75/5 stars

This is my second book from this author and when I saw romantic thriller I was definitely intrigued. In this one we follow Opal as she is returning home to her hometown to help her mother grieve the loss of one of her best friends.

I really loved the found family aspect of this one with the three best friends (mothers) that were so close and raised their kids (most of them) so closely.

Opal's plans derail quickly when she is forced to be roommates with her childhood "frenemy". We got flashbacks to learn more about their backstory. While these flashbacks and backstory were good and necessary at times, other times it felt like a little too much and more focus on the past than the present.

Let's add in the mystery of what really happened to her mother's friend. So many different accusations of what actually happened. What is the actual truth? I do wish that we did have some more focus on the mystery at times.

I was surprised with the twist and what happened! Definitely wasn't what I expected. Part of it maybe, but not all!

I listened to this one and the audio was single narration by Persephone Lee, and I feel like she did a great job with the story and all of the characters!

If you enjoy a romantic thriller with found family vibes, enemies to lovers, and some suspense, then definitely check this one out. Huge thanks to High Gravity Productions for the copy to listen to!

[Katy Fann]

I really enjoy Kiersten Modglin’s writing, but I didn’t love this story.

[Amanda Hopwood]

RTC

[Rebecca]

Head Under Water by Kiersten Modglin is a haunting, high-angst blend of psychological thriller and romantic suspense that weaves effortlessly between past and present.

The story follows Opal Sullivan, who returns home to help her grieving mother after the tragic loss of her best friend, Ruth. With plans to quickly find her own place and steer clear of her childhood neighbor and frenemy, Will Kendricks, Opal’s life immediately unravels when she learns her mother has rented her a room—with Will. Having shared a complicated history of best-friend mothers, bitter teasing, a buried past, and years of silence, Opal and Will are forced into close quarters. When questions and suspicious circumstances surrounding Ruth's death begin to mount, the pair team up to uncover the truth, navigating a tense small-town atmosphere where safety gives way to unease.

Blending an enemies-to-lovers romance packed with yearning, unresolved tension, and deep emotional stakes alongside a twisty mystery, the narrative keeps listeners guessing as past secrets threaten to resurface. The suspenseful listening experience is brought brilliantly to life through a phenomenal solo narration by Persephone Lee, whose strong distinct voices for each character and expertly paced delivery amplify the chilling atmosphere and emotional weight from start to finish.


Disclaimer: I received a copy of this book and am voluntarily leaving a review. All words and opinions are my own; no AI was used in writing this review.

[KKEC Reads]

Head Under Water by Kirsten Modglin
“For the first time, the future doesn’t feel like something to survive. It feels like something to step into.”

This was like falling into vintage KMod, and I am here for it. As fantastic as her thrillers are- her romantic thrillers are next level, and this did not disappoint.

I enjoyed this story. I liked how it was told, the alternating timelines and the way the characters develop as we go.

Something Kiersten does brilliantly is humanize her characters… they read as real people, with flaws and errors in judgment, and that feels so relatable.

I loved the depth to these characters, especially Will. I will forever be a Noah and Jesse girlie (iykyk), but Will is pretty dang great.

This story sucks you in. It is so layered and is very much a story within a story. I loved how the family is presented, and how the moms form a unified front, choosing to tackle life together. It takes a village, y'all.

This was a beautiful release from a writer we all know will never disappoint.

Publication Date: September 25, 2026
Publisher: Bitter House Publishing

[Christine M in Texas (stamperlady50)]

Happy Pub day @kierstenmodglinauthor You’ve done it again. This one is filled with tension, mystery, angst and is a unique romantic thriller. A fresh novel, not to be missed. 5🖤🖤🖤🖤🖤 It’s no secret I am a huge fan of this author and she’s an auto buy for me. She can’t write them fast enough for me. 😊

[Keri Smith]

Such A Good Story

I picked this up on release day and read it within a day! It was so good. Kept me hooked with each page. This novel was definitely more romance heavy than suspense but I enjoyed the heck out of it. 5/5 stars.

[Cindy Reddick]

I LOVED this book so much!! I have an aunt Opel and I’ve never met anyone else with that name, absolutely love the name Opel. The story starts off with a bang and continues to build. Kiersten writes in a way that makes you feel like you’re literally living the story. Another 10 star book for me ✨

[Aggie]

3.5 stars. I love Kiersten Modglin but this feels underwhelming for me. Although this will not stop me from reading her books.

[KathrynAlyse]

3.75 bumped up. A huge thank you to High Gravity Audio and author Kiersten Modglin for the ALC of Head Under Water 🖤

This was such an interesting romantic thriller! I’ll be honest the romance definitely seemed to overpower the thriller/murder aspect for me until about the 70% mark. I found myself wanting a little more mystery and suspense throughout the first part of the book, but that last 30% really helped make up for it!

Opal, our FMC, returns home after the death of one of the “moms” who helped raise her. And, of course, coming home means coming face-to-face with Will, the boy she grew up with and the ultimate frenemy who knows exactly how to get under her skin.

Will is THAT boy. The one who secretly loved her for way longer than he’d ever admit. Their romance was actually really sweet and packed with tension. There were definitely moments when I wanted to yell, “JUST KISS ALREADY!”

But the part that really pulled me in was the thriller aspect. I was intrigued by the mystery surrounding the death and kept wondering what was really going on. And that twist toward the end?! I LOVED it. It was shocking, heartbreaking, and sad all at once.

The narration was done entirely by Persephone Lee, and she did a fantastic job! She brought both the female and male characters to life and really captured the emotions, tension, and suspense throughout the story.

Overall, this was an intriguing romantic thriller with a sweet, tension-filled romance and a twisty ending that definitely kept me invested!

[Lb]

This is my first book by this author but it won't be my last, this story weaves through the past and present as Opal (FMC) returns home to be closer to her mother after a tragedy strikes, her mother's best friend passed away the police are ready to close the case and rule it as accidental but things are not adding up and Opal is determined to get to the bottom of what really happened.

I enjoyed this story, I did wish that it focused a bit more on the mystery at times as it spent a lot of time going back in time to Opal and Will's college days, and the mystery seemed to be put on the back burner and I wanted to know what was happening!

I did figure out some things before the end but I don't feel it took away from the story.

I thank the author and High Gravity for this ALC! It was single narration by Persephone Lee but she did really well with the story!

If you enjoy a romance with a mystery add this one to your TBR!

Book Blog: https://elbyslibrary.blogspot.com/202...

*High Gravity ALC *Mystery *found family *Teacher FMC *non-linear Narrative *Flashbacks

*Enemies --> More *thriller *small town *Secrets revealed

[Ainsley Rhodes]

Thank you to High Gravity Productions for this ALC!

I have read nearly 20 KM books & I love them for a quick thriller palette cleanser. They are fast paced, twisty and enjoyable. I also tend to go into books blind and just find out along the way, as I did with this one.

This story fell more into her romantic suspense category. It felt like a YA romance (dual timelines with college enemies to lovers) with a bit of a mystery at the end. More of CoHo vibes and less of a true thriller novel.

While it wasn't quite what I expected & took a little while to get into, it did keep me interested and entertained. The MMC was quite frustrating at times & I was able to predict the end when it came down to it.

The narration though? Done beautifully! The narrator was able to navigate multiple character voices and tones to a point that I didn't even notice there was only one person filling in both gender parts.

[Kahgreymom]

When I tell you I loved this book I am not exaggerating!!!!

Head Under Water is the first book I have read by Kiersten Modglin and I will definitely be reading more from this author.

Opal and Will are hilarious. My husband kept asking me what was so funny throughout this entire Book. The narrator, Persephone Lee does an amazing job. The tension between Opal and Will is undeniable and frustrating at the same time. I loved how the book is written in flash backs to show the relationship of the characters. You can really see the character growth during these flash backs. The mystery really kept me hooked and I had to know the resolution. I stayed up way too late to finish listening to this book, because I had to know the ending.

Will and Opal will always have a special place in my heart. If you love an enemies to lovers trope, with mystery and suspense, this book is for you!

[Helaine Lummus]

I loved this story! If a book can make me feel all the feels it’s a perfect read for me. And the Enemies-to-Lovers was perfect. There’s a “F-it” moment that is EVERYTHING. I really enjoyed both timelines and never got bored with either one, which doesn’t always happen for me with dual-timeline stories.

One thing I wasn’t expecting was the amount of times I would laugh. The banter between Williams and Opal was so funny. it kept butterflies in my stomach throughout the story. I loved them so much.

You need to listen to this book. Persephone does an amazing job narrating both the female and male characters. From her first sentence you will be hooked. This story grabs you and doesn’t let go.

[Michelle Bailey]

Head Under Water is a captivating thriller that starts in the present and delves into the past. Opal has come home to help her mother and teach at the local elementary school. She plans to stay with her on but instead rents a room from Will-her childhood frenemy. They decide to look into Ruth’s death and then things start to happen. More attacks? Who is guilty?
The solo performance by Persephone Lee was phenomenal. She portrayed each and every character perfectly. I highly recommend listening to this audiobook.
Thanks to the author and High Gravity Productions for this ALC.
AUDIOBOOK REVIEW: Story 5 stars Narration 5 stars

[☆Helen☆]

I’ve read Kerstin Moglin before, but only her thrillers, so I was NOT expecting this much romance. This felt heavily coated in romance with just a sprinkle of thriller thrown on top.
That being said, Moglin’s books are always fast reads for me and she knows how to keep my attention. Even though the romance was a little much for my taste, I flew through it and wanted to know what was going to happen.
So, despite all the lovey-dovey business getting in the way of my thriller 😂, I’m giving it 4 stars.

[Melissa Bova]

Loved

Has me kicking my feet. Gave me Hemlock feels! I’ve been waiting for this one! This one makes it to the trophy case!

[Lisa Nicholson-Davis]

Loved this one as much as I love her other books! Kiersten can't write fast enough for me! Great writing, story, twists, characters, and ending! Definitely recommend!

[Tropes_and_Taboo]

Head Under Water by Kiersten Modglin
⭐⭐⭐⭐ 🌶️
Romantic Thriller * Mystery * Grief * Childhood Enemies to Lovers * Roommates * Forced Proximity * Bully * Angst * Banter * He Falls First * Cheating * College * Found Family * Suicide (mentioned) * Miscommunication
📖315 pages 🎧9h25
🎙️Narrated by Persephone Lee (solo)
📆Expected release Sept 25 2026.

My first book from Kiersten Modglin. Although I occasionally pick up thrillers, they aren't often what I reach for. If you're someone like myself who can usually spot the twist before the reveal, this one I would classify as an easy one to decipher. However, as I didn't find it overly thriller-heavy, this may be why I quite enjoyed this.

Personally, I'm more of a romance fan, and this story truly wove in some great romance alongside the plot. Bouncing between flashbacks; the tension, banter, hate-to-love and love-to-hate moments kept me captivated. And while I knew how it would end, I was still all over the angst and frustration of her not seeing what was RIGHT IN FRONT OF HER FACE all along.

If people would just talk, they could've been together for years. But then I wouldn't get to indulge in angsty and fun stories. So I can't really complain. But in real life.. seriously, just talk to eachother.

The story is heavily centered around the Found Family trope. Family isn't always just biological. Having a village to help and support you, especially in troubling times, is such a benefit. The way this was portrayed, with them having three moms, three single friends who supported each other and took care of everyone like they were their own, was such a lovely aspect to see written on the page. This wasn't just a group of friends, these are the friends the kids call aunty.

The audio is in solo narration, and this was my first time listening to Persephone Lee. She was captivating, clear, and smooth throughout the story. I will happily listen to her again.

[Shelley]

Thank you High Gravity Productions and Kiersten Modglin for the ALC!

🎧 📖 Head Under Water by Kiersten Modglin
🎤 Performed by Persephone Lee
📚 Romantic Suspense!!
🌶🌶
🌟 🌟 🌟 🌟 🌟

~~

Head Under Water was absolutely perfect! I loved this book so much that I could NOT stop listening once I started.

The slow burn romance and tension between Opal and Will... whew! It was so good! Their banter and flirting was so funny. Their long history as friends/"frenemies" was just 🥹🩷

This has dual timelines and usually I feel like "ok, let's get back to the present timeline" but I enjoyed both the past and present timelines equally.

One thing I really loved (other than all of it) ~ The three mothers, their friendship, and raising their kids together. They had their own little village. And even though things weren't always perfect, they all looked out for each other.

The suspense was excellent because - are these women having accidents or is there something more sinister happening? The way that everything comes together is mind-blowing.

The performance by Persephone Lee was wonderful! I loved her voice and intense emotions. She did a great job with the male and female voices!! This was a terrific audiobook 🩷

Kiersten did an amazing job with this book! She has been one of my favorite authors for a long time and I will read anything she writes.

I hope there's more romantic suspense in the future! 🤗

[Ivey]

Kiersten Modglin delivers the perfect blend of romantic suspense and psychological thriller with this one. From the very first chapter, I was hooked by the mystery surrounding Ruth's death and the complicated history between Opal and Will.

Opal returns home expecting to help her mother heal, but nothing goes according to plan. Being forced to live with Will Kendricks, the one person she's spent years avoiding, creates an incredible amount of tension from the start. Their relationship is layered with hurt, resentment, unanswered questions, and undeniable chemistry, making every interaction feel charged with emotion. Just when I thought I had the mystery figured out, another twist sent me in a completely different direction. The small town setting felt both comforting and unsettling. Will was such a fascinating character. The more layers that were peeled back, the harder it became to decide whether he was someone Opal should trust or fear. Their enemies to lovers journey was packed with angst and yearning.

The single narration by Persephone Lee was phenomenal. She captured Opal's grief, vulnerability, determination, and frustration so well. Thank you, High gravity, for the ALC.

[Latasha]

This was such an interesting mix of romance, mystery, grief, and small-town secrets! I really liked the whole setup of Opal coming home to help her mom, only to find herself living with the one person she was determined to stay away from… Will. 😅 And of course, nothing stays simple once they start digging into Ruth’s death.

I really enjoyed the tension between Opal and Will, especially with all their history and the things they’ve both been trying to leave in the past. There was definitely that I don’t trust you, but I also can’t stay away from you feeling, and I was here for it. The mystery kept me curious because the more Opal uncovered, the more questions I had about what really happened.

There’s also a good emotional layer with the grief and the complicated relationships between the characters. I liked watching Opal try to make sense of the past while dealing with everything happening in the present.

I listened to the audiobook narrated by Persephone Lee, and I really enjoyed her narration. She did a great job bringing the characters and the tension of the story to life, and it made this an easy audiobook to settle into.

If you enjoy romance mixed with secrets, old wounds, small-town mysteries, and a little danger, definitely give this one a try.

[Debra Ramos]

Three moms. Mysterious "accidents" One question: Who is telling the truth?

Mysterious, charming, and packed with chemistry, banter, yearning and tension, this romantic thriller kept me curious from the start.
I especially loved the three moms raising their children together, that family dynamic was easily one of my favorite parts! There was something so warm and special about their bond, even with all the darkness surrounding the story.

The suspense had me wondering: Are these women really having accidents... or is someone behind the "accidents"? The piesces came together well, although I did wish the mystery had a little more focus at times.

The audiobook deserves a shoutout! The narrator absolutely nailed the single narration. Her male and female voices were strong, her tone and delivery brought an extra layer of tension to the story. Even with the time jomps, everything was easy to follow. Honestly, her performance was amazing creating more suspense that the mystery itself.

Overall: It was a great romantic thriller with plenty of secrets, family dynamics and tension. And if you are an audiobook lover, this narration is definetely worth experiencing.

Thank you tho the author and the picture of romance for the ALC, this is my honest review.