The Third Girl

by S.C. Shannon

Twenty-five years ago I escaped. One of us didn't.

Penelope, Emily and I were best friends growing up in the picture-perfect town of Tranquility Ridge. Pine-lined streets, quaint diners, creaky porch swings. The kind of place where nothing bad is supposed to happen. But the night before my seventeenth birthday, Emily invited us to a party, and everything changed. That's when we were taken.

Genres: Thriller

306 pages, Paperback

First published May 28, 2025

About the author

S.C. Shannon is an award-winning thriller author and law enforcement professional whose work blends psychological suspense with real-world crime experience. Her debut novel, THE THIRD GIRL (Joffe Books), earned two BookFest Awards, an International Impact Book Award, and a Reader’s Favorite Honorable Mention. She holds degrees in criminal justice and forensic psychology and is currently pursuing an MA in Writing at Johns Hopkins University. Her next psychological thriller, THE MISSING HOURS (Joffe Books), arrives in September 2026.

You can follow her on Instagram @s.c.shannon.author

Reviews

[Trin ˖ . ݁𝜗𝜚. ݁₊ · Rating 2 out of 5]

2⭐️

Pre-read: I’m in the mood for another thriller and I hope this delivers so I can binge it on the plane tmr 🤞🏼😋

I didn’t binge this on the plane.

Hi, hello **spoiler**
YOU’RE TELLING ME PENELOPE DIDN’T GO TO JAIL AND CHRISTINA FORGAVE HER FOR KIDNAPPING, TORTURING, AND RUINING HER LIFE??? NO JAIL? NO FEDERAL PRISON??

Ending was 😒. Dialogue was cringey and overused “!” Seemed like every conversation was straight yelling. Also, super slow up until 70%. Twist was predictable and boringgg🥱

[Mickey · Rating 4 out of 5]

Penelope, Emily and Christine were best friends from childhood until they were 16. That summer, everything changed. Penelope and Christine were kidnapped, put through Hell, but with help from Penelope, Christine managed to escape. Only when she took the police back to the house she'd been held in, no one was there.
25 years later, Emily is dead. Her husband has left a note for Christine, saying Penelope is alive. Now Christine has to go back to her hometown to finally find out who kidnapped them and why, and what happened to her best friends.

This book had me turning the pages so fast to start with. It was fast-paced, and twisty. I did figure out all the twists fairly early on, but that didn't really take away anything from my reading experience. What did really bug me, and it's such a silly thing, was the over-use of exclamation marks! Every other sentence spoken had one at the end! And it was becoming a little annoying tbh.
It was my first from this author and I look forward to reading more.

[Leah Golder · Rating 1 out of 5]

Very promising premise which made for a great thriller but this just fell flat for me!

No development of characters, all relationships and friendships were surface level with very cringey dialogue, and plot twists you could see a mile off.

And the ending just evoked pure frustration for me. Very rushed - everything happened in the last 30% after an almost mindnumbingly slow journey to get there. So unrealistic with the events that happened and such a ridiculous reunion between two characters who would never come back from the events that happened.

Promising premise and interesting idea but execution was very poor.

[Trina 🌻 · Rating 5 out of 5]

WOW!! I binged this book within 24 hours! Once I started reading I was hooked! Fast paced, full of suspense, I was on the edge of my seat waiting to see what happened next! And lots of unexpected twists! The authors writing style made this a fast and easy read. I am definitely going to search for more of her books!

So glad I had the opportunity to read the ARC, thanks to the author.

[Hot Mess Book Lover · Rating 4 out of 5]

"The Third Girl" is a sensational read that brilliantly captures teenage angst and showcases impressive character development. Shannon skillfully builds tension and suspense throughout the story, utilizing a nonlinear narrative with multiple points of view that keep you engaged and guessing. I devoured this book in no time and loved every moment of it. Highly recommended for anyone looking for a captivating and fast-paced story!

[Hannah Boyland · Rating 4 out of 5]

This book was one heck of a rollercoaster!

I like that Christina’s character was openly struggling with the trauma of what she’d been through. I do find it difficult reading thrillers when the characters are seemingly unphased by traumatic events - I know we all react different but to see someone in a book that isn’t just ‘strong’ the whole way through is actually quite refreshing.

This book flips between before and after, and in the before it also has the POV of the 3 FMCs - in theory I love this set up, but as a dyslexic with memory issues, I admittedly did find myself getting characters mixed up (but that’s a me problem🤣).

Some of the twists and turns were so unexpected! And I liked how fast paced this book was, but it also had the right amounts of suspense at the same time.

I really liked SC Shannon’s writing style - I don’t know how to explain, but it felt like simplistic language was used, but not in a childish way? I often find it hard to process things, but the language/style of this felt perfect!

I definitely need to read more of SC Shannon’s books!!

[Joanne · Rating 2 out of 5]

Book for teenagers

[Phil Rogers · Rating 4 out of 5]

A psychological thriller from a great storyteller.

Three schoolgirls Emily, Penelope, and Cassie are growing up in the quiet and safe backwater of Tranquillity Ridge, the name says it all. As teenagers, they go to a seventeenth birthday party looking for drink and boys. That's when it all goes wrong.
Cassie wakes up chained to a bed, gagged and blindfolded. After a time, she's woken by penelope, who frees her and tells her to run. she runs and leaves Penelope behind to face the captors. Emily is also missing .
Cassie faces years of guilt at abandoning Penelope, who she assumes is dead and becomes a virtual recluse with only her dog for company. That is until she receives a note . It's in Emily's handwriting and tells Cassie that Penelope is alive and she must find her. The lies and twists make this a compulsive page turner as Cassie sets out to discover the truth.

[Rary ⏾ ❤︎ · Rating 3 out of 5]

ARC READ - NetGallery

A friend group bound by secrets waiting to be uncovered.

Each Before chapter should use the past tense just as the other chapters use the present.

One inconsistency stood out. The body in the ground. They took the teeth for DNA but at the end of the book she had no teeth at all. I’m so confused.

I didn’t like the ending. I’ll never forgive anyone for all the terrible things that happened. I wish it had ended differently.

[Jessica Huntley · Rating 5 out of 5]

⭐️⭐️⭐️⭐️💫
What a brilliant thriller! Only reason it's not 5 stars is that I saw the twist coming but I can't fault the tense writing, the excellent character development and the gripping story. At the end of every chapter, I wanted to keep reading and it held my attention from the start. Highly recommended.

[Kate Shelton · Rating 5 out of 5]

Wow! I was lucky enough to read this book early, and I loved it. It's one of those books that just kept me reading. I really loved the before-and-after timeline, as well as the different POVs. If you're looking for a thrilling thriller, don't miss this one!

[booked.with.julia · Rating 4 out of 5]

This one was dark, twisty, and emotionally layered in all of the best ways.
We follow Christina, who escaped a kidnapping 25 years ago that claimed her two best friends. One never came back. One JUST died… but not before leaving behind a cryptic note that the missing friend is still alive.
I absolutely loved the dual timeline. I was just as invested in the past as I was in the present, and the way the secrets unraveled kept me completely hooked.

[Sonja Charters · Rating 4 out of 5]

This one drew me in from the start and I was hooked right to the last page.

 

It was my first read by this author, but I really loved the look of the front cover with that hint of blood, promising a mystery.

 

The story really plunges us in head first from the start and this pace never lets up throughout. I found it really hard to put this one down.

 

I instantly felt for poor Chrissie.

After surviving the ordeal of being kidnapped along with her friend, all those years ago, she still lives with the consequences - as expected - but having that added survivors guilt too, means that she just can't move on and live life to the full.

When she returns home to attend Emily's funeral, everything is dragged back into the forefront again as she discovers that Penelope might still be alive after all.

 

This kept me guessing and was so twisty. I kept coming up with ideas and theories about what happened and who might have been involved - and I did get some of the twists earlier on, but this still didn't spoil my enjoyment of the storyline at all.

 

The writing style created a great atmosphere and had me on edge and racing to find out what was going on and where Penelope was, if she was alive still.

 

A great read and an author that I'd love to read more of in the future.

 

[Findapassion1114 · Rating 5 out of 5]

"What I regret most is feeling like I had to choose between friendship and love."

Special thanks to the beta copy from @s.c.shannon.author

𝙈𝙔 𝙍𝙀𝙑𝙄𝙀𝙒:
⭐️⭐️⭐️⭐️⭐️

Ok okay OHKAY! so I LOVED her first book and i was honored to beta read this one for her. It was so twisted, suspenseful, and unhinged!

My jaw dropped at the ending, like wow.
This is another installment i guarantee will have you on the edge of your seat until the ending.

Preorder this one asap!

𝙋𝙐𝘽 𝘿𝘼𝙔:
June 3rd, 2025

[Abbey Walsh · Rating 2 out of 5]

This could’ve been good but the writing style was brutal. So many ! and phrases no one would use in normal conversation. Also nothing substantial happened till the very end

Could’ve been a good storyline

[Karolyn · Rating 5 out of 5]

Here is my review for The Third Girl by S. C. Shannon

This was a brilliant psychological story that hooked me right from the start of the book. The story involved three best friends : Penelope, Emily and Christina. They usually hung around together. One night, Emily invited Penelope and Christina to a bonfire night and they were all meant to meet there at 9pm. Penelope and Christina went together to the location and were kidnapped from there twenty five years ago. A few weeks later, Christina manages to escape but her life was changed forever. After receiving a note from Emily to say Penelope is still alive and to find her, Christina’s mind is spinning so she decides to try and find her. She goes back to Tranquility Ridge and starts searching. This story is superbly written and really well plotted. There are a lot of twists and turns in this story to keep you guessing. The story is told in the present and the past. Both time zones are told from all three characters' viewpoints. I like books like this. This story was a really intriguing suspenseful read and was full of tension. The three characters were written exceptionally well with a lot of good details included. The other characters were written well too and helped make this an exceptional read that I just couldn’t put down as I had to know what happened next. The descriptive text and detailed writing helped me picture this story in my mind as I was reading it. I liked the author’s writing style which was very easy to read. I liked the synopsis which drew me to read this book which I loved immensely. I look forward to reading more stories from this author in the future.

Blurb :


Twenty-five years ago, I escaped. One of us didn’t.

We were best friends — Penelope, Emily and me — growing up in the picture-perfect town of Tranquility Ridge. Pine-lined streets, quaint diners, creaky porch swings. The kind of place nothing bad is supposed to happen.

But the night before my seventeenth birthday, everything changed.

Emily invited us to a party.

That’s when we were taken.

I woke up shackled to a rusted metal bed. My wrists bled. My ankles bruised. Music blared around the clock — too loud, too cruel. I never saw who did it. I was trained not to look.

I escaped.

Penelope didn’t.

And Emily? She’s been lying ever since.

Now, twenty-five years later, a stranger appears with a message, scrawled in Emily’s handwriting — a message I never expected to read:

Penelope’s alive — find her!

A RAZOR-SHARP PSYCHOLOGICAL THRILLER PACKED WITH BURIED SECRETS, BRUTAL TRUTHS, AND TWISTS YOU WON’T SEE COMING.

[Paula Phillips · Rating 4 out of 5]

There's something irresistible about a thriller that weaves between past and present, unraveling secrets that have festered for decades. When I first glimpsed the cover of The Third Girl by SC Shannon, I immediately screenshotted it—something about the atmospheric design whispered that this would be exactly the kind of psychological thriller I devour. When Zooloos Book Tour announced their virtual tour for this novel, I didn't hesitate to sign up, and I'm thrilled to say the story delivered on every promise that haunting cover made.

SC Shannon masterfully constructs a narrative that begins twenty-five years in the past with three inseparable friends whose lives are shattered by a terrifying kidnapping. Penelope and Christine are taken, but when Penelope stabs their captor and Christine escapes to summon help, the police return to find an empty house—no Penelope, no kidnapper, just questions that echo through the decades.

The present-day storyline ignites when Christine receives an unexpected message following Emily's death. Emily, the third member of their childhood trio, has left behind a bombshell revelation: Penelope might still be alive. This discovery propels Christine back to her hometown for Emily's funeral and into a labyrinthine investigation that forces her to confront buried trauma while questioning everything she believed about that fateful night.

What sets The Third Girl apart is SC Shannon's ability to maintain tension across both timelines without sacrificing character development. Christine's journey from survivor to seeker feels authentic and emotionally resonant. The supporting cast of former friends who aid her investigation adds depth to the small-town atmosphere, creating a sense of community shadowed by long-held secrets.

The revelation of truth comes with devastating implications about trust and betrayal. SC Shannon doesn't shy away from exploring how those closest to us can sometimes be complicit in our darkest moments, making the emotional impact all the more powerful. The novel reminded me strongly of Kate Alice Marshall's What Lies in the Woods—both books excel at examining how childhood trauma ripples through adult lives.

This was my introduction to SC Shannon's work, and I'm already eager to explore their backlist. If The Third Girl is any indication of their storytelling prowess, I suspect I've discovered a new must-read author for my thriller collection.

[Padmajha [PJ] Me and My Bookshelf · Rating 5 out of 5]

The Third Girl is a fast-paced psychological thriller that grabs you from the first page and never lets go.
Centered around three childhood friends—Christina, Emily, and Penelope—the story explores the long-lasting impact of a traumatic event that shattered their lives.
Christina receives a cryptic message and decides to check it out. When she returns to the same town where it all began, she's forced to confront the ghosts of the past. But what really happened to Penelope? And can the others ever truly heal, physically or emotionally? This is the crux of the story.
Told through three distinct points of view and weaving between past and present timelines, the narrative is layered yet flawlessly constructed. Despite the multiple perspectives and shifting timelines, the plot remains sharp, coherent, and utterly engrossing. I found myself flying through the pages, completely absorbed, and read the entire book in one sitting.
The author masterfully builds suspense—each chapter ends with a cliffhanger that urges you to keep going. Everyone seemed suspicious at first, yet somehow appear innocent as the story unfolded.
The final twist? Completely unexpected and chilling. The culprits were shockingly ruthless, and the reveal left me stunned.
What I liked most was how vividly each character was brought to life. Emily’s inner turmoil, Penelope’s resentment toward her mother, and Christina’s teenage crush on Ryan—all felt authentic and relatable.
Christina’s struggle to reclaim a sense of normalcy after the kidnapping is portrayed with raw emotion and depth. Her trauma feels real and relatable, making her journey all the more compelling and heart-wrenching.
Even the minor characters had weight and purpose in the plot. The flashbacks to the girls’ youth were especially well done, with nostalgic touches that reminded me of my own teen years—until things took a dark turn.
This book highlights how easily a situation that began as a harmless prank but spiraled horribly out of control and turned into something far more sinister. The Third Girl isn’t just a crime thriller—it’s a haunting exploration of memory, trauma, and the choices that shape us.
If you're in the mood for a tightly written, emotionally charged thriller that keeps you guessing until the very end, this one is definitely worth picking up.

[janine · Rating 5 out of 5]

You know how some books land in your TBR pile at the perfect time? That is just what happened with this book. I wanted, no, needed a tense, thrilling, explosive read, and that is exactly what this book delivered.

This is the first book I have read by this author, but it won’t be the last. Her writing style was phenomenal. It had me hooked within minutes, and the fast paced execution made it such an easy read.

Told on dual timelines of ‘before’ and ‘after’ and through the narrative of three POVs, this is one hell of a rollercoaster.

Three schoolgirl best friends, Emily, Penelope, and Christina are living their teenage lives in the safe haven of Tranquillity Ridge but their friendship is fraught with abusive home lives, secret relationships, and the change in friendships as they grow older. One night, two of the girls are abducted, and weeks later, only one escapes. Life will never be the same again.

Penelope never escaped. Their abductors were never caught.

Years later, Christina has lived her life as a recluse, feeling the constant agonising guilt of leaving Penelope behind, and she was never found. She receives a note through the door from Emily’s husband. Emily has died but instructed her husband to find Christina and pass on her bombshell message... ‘Penelope is alive. Find her’

This revelation comes with a host of devastating consequences. The only way Christina can find the truth is by going back to her hometown, a place she hasn’t revisited since she escaped. Will her survivors guilt hinder her, or can she move past it to finally understand what happened that fateful night 25 years ago.

Arriving in her hometown for the funeral, she reconnects with Emily’s brother, who also happens to be her first love. He promises to help Christina investigate, and they start to visit old friends, acquaintances, and the officers who were involved in the original investigation.

This is a plot brimming with suspense, twists, unexpected turns, and tension. The originality was superb, I thought I had it all figured out, but I was wrong time and time again.

Huge thanks to Netgalley and Joffe Books for the ARC.

[KZ · Rating 2 out of 5]

★★☆☆☆ (2 stars)

The Third Girl by S.C. Shannon seemed like it had the potential to be a meaningful and emotional story, but unfortunately, it didn’t land for me. I only made it about 35% through before deciding to stop, which is something I rarely do. Still, I gave it 2 stars because I recognize that the premise held promise—I just couldn't get past the execution.

The story touches on themes of identity, mystery, resilience and suspense. It also shows a representation of living with scoliosis (briefly), which is a unique and important subject to bring attention to. I appreciated the attempt to shed light on that experience, but the way it was handled felt jarring. Conversations around the condition came across as forced and out of place, almost like they were inserted to make a point rather than integrated naturally into the characters’ lives. It lacked the emotional grounding needed to make those moments resonate.

My main struggle, though, was with the writing style. It felt extremely amateurish, and there were multiple punctuation issues that broke the immersion. Most notably, exclamation points were used far too often—even in situations that clearly didn’t call for them. It made the dialogue feel overly dramatic or unintentionally awkward, which undercut the tension or seriousness of certain scenes. The prose also didn’t flow well; it felt clunky, with transitions that didn’t quite work and pacing that dragged in places where it should have pulled me in.

Despite the interesting concept, I just couldn’t connect with the characters or the storytelling. The narrative voice never fully found its footing, and I wasn’t compelled enough to push through to the end. It's clear the author wanted to tell a suspenseful mystery with tension and heartbreak, but for me, it needed more polish, a better grip on tone, and a smoother delivery to make it truly effective.

Tropes & Themes You’ll Find:

✅ Family Secrets
✅ Quiet Trauma
✅ Female Protagonist
✅ Small Town Setting
✅ Friendship & Isolation
✅ Medical Awareness Issues

[Vanessa · Rating 5 out of 5]

The Third Girl by S.C. Shannon just drew me in from the beginning till the very end and I really enjoyed it. this book was full of twists and turns and became a very twisty psychological thriller with great characters.

Emily, Penelope, and Cassie have been friends since their childhood and now they are all turning 16 and they all went to school together. They are growing up in the perfect but quiet safe place of backwater of Tranquillity Ridge, a picture perfect town, with pine-lined streets, quaint diners, creaky porch swings. what more could you ever want? this was a perfect place to grow up in. It's now the Summer time and they all go to a seventeenth birthday party and are all looking for drink and fun and especially boys.!!!

What could ever go wrong? It's just a party?

But, That's when it all goes wrong.

This is when everything changed for all of them! Penelope and Christine were kidnapped. . . . . . . . . They did not know where they were and they were put through Hell! Christine managed to escape, with with help from Penelope and she ended up running to the closest house she could find to get help!
When Christine got there she explained she and Penelope has been kidnapped, the owner of the house phoned the Police. Christine was distraught, took the police back to the house she'd been held in, But, there was no one there.

Where is Penelope?

Now, 25 years pass. . . . . . . .and Emily is dead. Her husband visited Christine's house and she would not answer the door to strangers. He has puts a note through her day. . . . . . Saying "Penelope is alive."

But is Penelope really alive or it this a hoax?

They only way Christine is going to find out, is to go back to her hometown and where it all happened!. to find out what happened to them both. . . .

Sadly Christine, has a fear leaving her house because of what happened all those years ago now,

Excellent book. Loved it

[Pav S. (pav_sanborn_bookworm) · Rating 4 out of 5]

Christina reflects on an escape from a traumatic incident that occurred twenty-five years ago, detailing the bond between best friends Penelope, Emily, and Christina in the idyllic town of Tranquility Ridge. Their lives take a dark turn the night before the narrator's seventeenth birthday when Emily invites them to a party, leading to a harrowing event that takes them away, marking a pivotal change in their lives.

This book was fast-paced, and I was initially drawn in by the cover, which was a pleasant surprise. It shifts between timelines, allowing us to piece together the full story of what actually happened. The narrative is told from multiple points of view, primarily focusing on Christina, Emily and Penelope, three friends experiencing typical teenage life in the 90s. Christina is a relatable character, and I can understand how difficult life became for her after everything she went through. It’s hard to imagine how someone can simply move on after such trauma.

The other characters are less likable and tend to fit the mold of typical teenage drama queens. I found myself guessing throughout the book, unable to put it down. I needed to know who the perpetrator was and why they acted as they did. This story keeps you on the edge of your seat, as it reveals the dark truth of how cruel friends can be.

If you enjoy trying to guess the culprit, reading about complicated friendships in a small town, and encountering unpredictable endings, this book is perfect for a rainy day! It’s easy to binge-read, and you won’t see the main twist coming. I truly felt sad for Christina and what she endured—it's disheartening to consider what she faced. Overall, this was a great read, but the plot was disappointingly realistic. Unfortunately, people can behave like this. I hope you have better friends than Christina did!

Thank you, Thriller Book Lovers the Pulse, for the digital ARC copy. I am leaving this review voluntarily.

[Lakelynn Wild · Rating 5 out of 5]

Three Friends, One Town, and Secrets That Won’t Stay Buried---and I Was Right There With Them!

I was lucky enough to be an ARC reader for The Third Girl by S.C. Shannon, and what a privilege it was to read her third book early!

S.C. Shannon's third book is an absolute standout! I was completely drawn in by the dual timeline, which was seamlessly woven and kept me turning pages late into the night. The dynamic between the three friends felt so genuine and relatable. It was easy to see pieces of myself and people I know in each of them. I also loved all the '90s music woven throughout. It took me right back to my teenage years in the best way!

As a mental health therapist, I was especially moved by Christina’s character. Shannon’s portrayal of trauma and grounding techniques in the face of PTSD was not only accurate, but deeply respectful and powerful. Christina’s journey was one of the most compelling parts of the book, and the author’s consistency in presenting her coping strategies made me feel both grounded and emotionally invested.

The suspense is masterfully crafted. I was kept guessing until the very end about who was responsible for the kidnapping of the two girls. Just when I thought I had it figured out, Shannon surprised me with another twist that made me question everything.

Her writing is concise, evocative, and perfectly paced. I could vividly picture Tranquility Ridge. I felt like I was walking its streets alongside the characters. As someone who loved The Girl No One Loved, I was thrilled to spot the subtle nod to her debut in this book.

S.C. Shannon is quickly becoming a must-read author for me. I can’t wait to see what she has in store for book four. If you enjoy layered mysteries with emotional depth, authentic characters, and gripping suspense, The Third Girl is one you won't want to miss!

[Julie (JuJu) · Rating 5 out of 5]

🔪ARC Review: The Third Girl by S.C. Shannon🔪
🌟🌟🌟🌟.5
Hey, thriller fans! Huge thanks to @ThrillerBookLoversThePulse for putting this awesome find on my radar! If you’re looking for a psychological thriller that’ll have you questioning every page, you need to check out "The Third Girl."

It’s OUT NOW and free on KINDLE UNLIMITED! Right from page one, this book grabbed me with the intensity of a cold hand in the dark (serious chills!). With its dual timelines and multiple perspectives, it unravels a mystery that took place twenty-five years ago. We zip back to the summer when Christina and Penelope were snatched, then fast forward to today when Christina’s back in her hometown after yet another curveball life threw her way.

Just when she thinks she’s finally got a handle on things, the past pops back up like an unwanted ex at a party. Could Penelope still be alive?

Shannon captures the claustrophobic small-town vibe and the emotional chaos of surviving trauma with perfect precision. The switching perspectives add a delicious layer of intrigue.

The girl power vibes in this story are right on point! I fell in love with the tangled web of relationships among the three teenage girls! They had me reminiscing about my own cringeworthy high school days that I kind of miss (but don’t want to relive). The plot twists are like a thrilling, terrifying spin on a carnival ride that whips you around and then leaves you gasping at the grand finale! 😱😍

Grab this one, and your weekend plans just got way more exciting! 🕵️‍♀️📚

Thanks to the author and Joffe Books for providing this eARC via NetGalley. All opinions are my own.

[Alison Taylor · Rating 5 out of 5]

A fantastic book. It starts straight away. The very first chapter had me gripped. It explains how Christina manages to escape from her captivity. Elated and desperate she feels guilty for having to leave behind Penelope. The book goes through the difference in timelines. Some of the chapters explain what led up to the girls being taken and the reasons behind it. The other chapters focus on Christina and how her survivors guilt and trauma have changed her. Both as a person and how she lives her life. Her life is much more about existing rather than living. A letter comes through her door one evening it says 'she's still alive find her! Although desperate not to have to revisit her past she understands she needs closure. So she begins her journey into looking at what exactly happened to her and more importantly could penelope still be alive. This is a journey that unfolds for Christina as well as the reader. The author has done this in such a clever way with the way the chapters reveal exactly what happens. The author really zooms in on each and every character particularly what motivates each character. The way in which the author writes about the traumatic events it sounds very true to life. Therefore it is an emotional read. The ending was the icing on the cake for me. It was simply brilliant. There is nothing negative I can say about this book. It is quite simply brilliant. You will not be disappointed!

[Jo ♡︎ · Rating 4 out of 5]

“The three of us were links in a chain, bound and unbreakable. Looking back, however, I can’t help but recognize the rust that had been forming on that chain.”

--

This is a haunting psychological thriller that lingers long after the final page. Told in alternating timelines between past and present, the novel follows Christina Johnson, a woman who escaped a harrowing abduction as a teenager while her best friend, Penelope, was never found. Now, decades later, the sudden death of their mutual friend Emily brings an unsettling message to Christina’s doorstep... "She’s still alive—find her."

What I loved most about this novel is how deeply it explores the aftermath of trauma. Christina’s PTSD is portrayed with such realism and sensitivity—from her coping rituals to her paralyzing flashbacks—that it grounds the story in emotional truth. However, the pacing did waver in the middle. And while Christina’s character was fully fleshed out, the voices of Penelope and Emily occasionally blurred together in the past chapters.

With its emotional depth, steady suspense, and raw portrayal of survival, The Third Girl is perfect for fans of Lisa Jewell, Dot Hutchison, or anyone who enjoys thrillers with a strong psychological edge. It’s not just a whodunit—it’s a story about what happens after, and how some truths refuse to stay buried.

[Lisa · Rating 5 out of 5]

When a dedication to a book is “For those who prefer their stories dark, their plots twisted, and their nights sleepless—this one’s for you!”—you better believe it. I was not prepared for the outrageous twists and turns with this novel. My jaw dropped throughout most of the ending and I for the life of me could not figure out the villain(s) early on. S.C. Shannon did a phenomenal job at creating characters and scenes that had you guessing the entire way. With having three point of views from the past, it was such a great way to make the story. The “present” views were all from the main character Christine and that woman had gone through hell. This was such a good thriller novel and it had me questioning everything and being completely wrong so many times. I flew through this in less than 12 hours. Props to the author for creating such an imaginative, heart pounding, mysterious, and emotional story. Highly recommend!

I received this book as an ARC and in return gave my honest opinion.

[Meg · Rating 3 out of 5]

Thank you to the author and publisher for allowing me an ARC of this via NetGalley! This did not influence my review.

This book is a good little crime/mystery book about three best friends who become involved in a tragic and dark crime. There were some really interesting plot twists, and I really liked the throwbacks (LimeWire in particular!). It was pretty easy to follow and it felt like a good representation of the complexities of young friendships.

Some parts were predictable and I found that this didn’t really have me ‘hooked in’. There were times where the plot felt slow and I struggle to read it, then it suddenly picked up and a lot of things were answered at once. There were also some phrases which just felt a bit repetitive and out of place at times. There were a few missed opportunities to expand on some of the character’s stories which made them hard to connect with and difficult to differentiate.

Overall, I think crime/mystery fans will adore this book!

Rating: 3/5 stars ⭐️⭐️⭐️/⭐️⭐️⭐️⭐️⭐️)

[Joanne Lewis · Rating 4 out of 5]

The tagline really does deliver on this one; it truly is a nail-biting crime thriller!

Set in chapters alternating between the past and present, author S C Shannon cleverly crafts an intriguing tale of teenage friendship and angst, dark family secrets which impact heavily on future actions and a gripping present-day thread that provides plenty of potential suspects but keeps the reader guessing until the nervy climax.

Written in an easy-to-read style and with plenty of cultural 90s/ 00s references to add relevant context, it’s easy to fly through the pages. There was also enough hints in the past about Penelope to keep me curious as to what part she had played in events and I found myself torn between loathing her teenage personality and empathising with her position due to the treatment she received from her mother.

A twisted, thought-provoking thriller. This is my first read from this author but I will be keeping a close eye out for future releases!

With thanks to the author, Zoe at Zooloo’s Book Tours and Joffe Books for the opportunity to participate in the tour.

[Aly · Rating 4 out of 5]

This was a really great read that scratched my mystery and suspense itch. The story follows Christine, who was kidnapped and tortured as a teenager along with her best friend, Penelope. Christine escaped, but Penelope was never found. Decades later, Christine begins to unravel the cold case, with the book alternating between her present-day investigation and flashbacks to her teenage years filled with crushes, friendship drama, and family tension.

The plot twist was excellent and tied everything together in a satisfying way, explaining what really happened to Penelope and why the case remained unsolved. My only issue was with Christine’s character—while her strength is admirable, I found her choices at the end hard to relate to. Without spoiling anything, I wish she hadn’t forgiven certain people so easily after everything she endured. Still, it’s a powerful story about trauma, resilience, and reclaiming one’s life.

If you enjoy mysteries with emotional depth and dual timelines, this is definitely worth reading.