Riding the Line

by Sarah K. Mason

She knew the assignment would be dangerous. She didn’t know it would change her life.

Detective Katie McGrady has trained for every situation imaginable—but nothing prepares her for going undercover as Nicole Moore, a hardened woman with a fake rap sheet and a chip on her shoulder. Her infiltrate the Steel Saints Motorcycle Club and get close to the DiAngelo crime family. Her don’t break character, don’t trust anyone, and definitely don’t fall in love.

Then she meets them—Dalton and Maverick. Two brothers. One’s all Southern charm and quiet strength. The other is fire, fury, and untamed loyalty. Both see through her walls, and both threaten to burn down everything she’s built to protect.

As Katie navigates a world of roaring engines, buried secrets, and found family, the lines between right and wrong blur—and so does the line between who she’s pretending to be and who she truly is. But danger is closing in fast, and the deeper she falls, the harder it will be to walk away.

Riding the Line is a high-stakes, emotionally charged romantic suspense with morally gray heroes, a badass heroine torn between duty and desire, and the kind of found family that fights for their own—no matter the cost.

286 pages, Kindle Edition

Published August 9, 2025

About the author

Hey there!
I’m Sarah — Missouri based romance author, chaos enthusiast, and snack provider for tiny humans and critters of all shapes and sizes.

I write high-stakes, high-heat stories full of found family, emotional damage, and morally gray men who’d burn the world down for the people they love.

When I’m not writing? I’m running on coffee and binge-reading in the few quiet moments I can find admidst the chaos that is home.

In all seriousness, creating the Steel Saints universe has been an absolute thrill. I can’t wait to fan girl with you! And to see what the future has in store.

Follow me on Insta or Tiktok!
@sarahkmason_author

Or take a look at my website.
https://sarahkmasonauthor.com/

Reviews

[Doris · Rating 5 out of 5]

Loved It

Now that the badge is off Katie is working to bring down a child trafficking ring and do what needs being done. When she is led to the Steel Saints MC where Dalton and Mac are members she finds more than just information. When the time comes will she be able to make the hard decision.

I loved this MC book with the drama, action and steam and look forward to reading more from this author.

[Laura Jean · Rating 4 out of 5]

This book sucks you in from the very beginning and keeps you entertained until the end. I loved the FMC and the MMCs. I laughed, gasped and read until I couldn't keep my eyelids open.

The main character, Katie McGrady (Nicole Moore) is a badass and never let's anyone or anything get her down for too long. The MMCs were morally grey for all the right reasons and I really liked the connection they made with Katie throughout the book.

I received an ARC for this book and I'm so glad I did. I was scared at first because I've been having such bad luck with ARCs lately, I've felt like I have been cursed. This book really turned it around.

If you like badass FMC, swoon-worthy MC MMCs, action, heart with the right amount of funny, you'll love this book.

[Leigh's Little Library · Rating 5 out of 5]

I am beginning to realise I love Biker romances.

The story was engaging, and the characters were likeable, which made reading it really easy. It pulls you in as Katie/Nicky falls deeper into biker life, questioning her future.

I love the why choose element and the found family theme. Pacing at points, I thought it was maybe a bit rushed, but other than that, I couldn't put the book down.

I always get knots in my stomach thinking about the final act when the secrets are uncovered and identities are revealed, and I loved the ending.

It has dark themes, but violence on the page isn't overpowering.

It's on the milder side of some of the other Biker romances I've read, but it was quite refreshing. One for beginners of the genre but definitely worth the read. I could have kept reading more from the Saints Club house!

There were a couple of chapters from Mavericks point of view, switching things up a bit, but it would have been nice to hear a bit from Dalton, too.

I will absolutely be reading Holly and Jackson's story 😍

[Merry One Maria · Rating 4 out of 5]

A gritty story for Katie, Mac, and Dalton

This book was a surprise, in the best storytelling way. There is a note from the author in the front to mind triggers. This story follows a lieutenant Katie aka Nicky on an expected undercover assignment. Katie had not been trained nor had any experience but she was determined to bring to justice those who were stealing females in her town. Guess what? Katie finds out life is not always black and white, it is definitely filled with variations of gray. There are some serious moments, laughs, fights, spill the tea sessions, and big surprises. Read On!

[Ann L · Rating 4 out of 5]

I really enjoyed Riding the Line. Katie is such a strong character, and I loved watching her struggle between staying true to her mission and following her heart. The mix of danger, romance, and found family kept me hooked, and the two brothers added so much tension and emotion.

This is a fast-paced romantic suspense with characters who feel real and complicated, this is a great read.

[Casandra Shaffer · Rating 5 out of 5]

Riding the Line had me hooked from the first page! The characters feel real, the story moves fast, and the mix of tension and emotion kept me turning pages. Definitely a ride worth taking!

[Lisa Newton · Rating 5 out of 5]

Wow! I haven’t read a story like this in a long time. It grabs you from the very first page and just keeps getting better with every chapter. Katie is a strong, fearless heroine on a mission to take down a dangerous child trafficking ring. Her journey leads her to Dalton and Mac’s biker club, where she hopes to gather information—but what she finds is so much more.

As Katie digs deeper into the case, she also finds a sense of belonging and maybe even a family she never expected. But when she uncovers who’s really behind the trafficking, she’s faced with a painful choice: doing the right thing or hurting the people she’s grown to love.

Gripping, action-packed, and seriously steamy—this story has it all. Loved it!

[Molly Alshanski · Rating 1 out of 5]

Book 35 of the year. And truthfully this book was awful. There were so many plot holes and every other word was “I hope they can forgive me when this is all revealed in the end” it was just not my type of book at all.

[Lisa Wood · Rating 4 out of 5]

I would actually give the book 3.75 stars. I did enjoy the book but never fully engaged with the characters. The plot was good but only the final third/quarter of the book seemed to be about the missing children. Don’t get me wrong, I want the romance/spice (which was great), but felt it overpowered the rest of the story. And the agent/handler ‘sub-story’ came out of left field, like the main character said, if he felt that way, why did he not help her when she needed it?!

I received an advance review copy for free, and I am leaving this review voluntarily.

[Trisha Mae · Rating 4 out of 5]

This was amazing!! This had me in a chokehold the entire time. It was sooo well written. 

[Wendy Smith · Rating 5 out of 5]

WOW, what a long epic journey into deceit, danger, chaos, intrigue and love. Katie, Mac and Dalton’s story was amazing, I loved it ❤️❤️❤️ I was drained of emotions once I got to the end, my worry for Katie as I read this story, wondering if in the end she’d lose it all, would Mac, Dalton and Katie survive once the truth was out, my heart was double timing hoping they would as their love story was so beautiful. So excited for the next book. A definite page turner and very entertaining. 100% recommend this book to everyone ⭐️⭐️⭐️⭐️⭐️ you will not be disappointed 😎🖤

[Carolina Brady · Rating 5 out of 5]

What an amazing book! Great story line, good suspense and action. Had me falling in love with every single character! Completely sucked me in from start to finish. Dalton and Mac are beyond swoon worthy 😍😍😍. I cannot wait for the rest of the series!

[Joann Cutler · Rating 5 out of 5]

Worth the read! The job doesn’t stay the job… it becomes home. The people become family and family saves family!

[Laura Rioux · Rating 5 out of 5]

I enjoyed this book! I was on the edge of my seat half the time.
I got sucked in after reading the first chapter. It started with an action scene with the main character.
I thought the scenes with Mac and Dalton were perfect. It was very spicy. Perfect mystery too. Shows the real struggles of what being undercover could be like.
I really wanted this to be a movie while reading the book!

[Readernerd57_book_reviews · Rating 4 out of 5]

4⭐ 3🌶️ 4❤️

I received a gifted e-ARC and this is my honest review.

✨Review Highlights✨
- Great start of a interconnected stand alone series
- Why choose romance
- Motorcycle club romance
- Good plot
- Fast pacing
- Interesting characters
- I would recommend, and I would most likely continue the series

I liked this book, it had a good story around the romance and a good plot outside of the romance. I would say that the romance and the story were pretty even in this book. I was really interested in the characters in this story, not just the MMC's and the FMC but all the characters in the story. It is really the characters and how they were written that makes me want to continue this series. I felt a connection to all of them and want to know more about the side characters from this book.

In regards to the romance in this book between the MMC's and the FMC I was a little bothered by it. I felt like within the why choose dynamic that the FMC liked one of the brothers more then the other. I have never felt that way while reading a why choose before and it made me feel at times that it was going to go from a why choose to a love triangle and that she was going to choose one of them. I really didn't like that. I love that it stayed a why choose however I really feel like the FMC liked one of them more then the other. It didn't feel like a balance of love to me, others may feel different but to me if felt like there was more feelings for one over the other. Do I feel like she loved them both? Absolutely, it just didn't seem like she loved them both the same.

I liked the writing, but I will say that if felt like a debut novel and I don't know if that is what this is, that is just what it felt like to me. There were some grammar mistakes which I really don't care about, but there were some inconsistencies in the story that where at times confusing until I realized that they were most likely mistakes. I still really enjoyed the story and felt like the author had great pacing throughout the story, which can be hard to do when your book covers a span of time well over a year.

I would recommend people read this if they enjoy MC romances with a lot of angst and suspense. I really enjoyed the story and I really connected to the characters. The writing isn't the best I have ever read, but I felt the story. I felt the characters emotions and was invested to find out what happened to all of them. I feel like if an author can capture your emotions, that is the best writing I can ask for.

[Jaimie · Rating 4 out of 5]

If you love a good MC romance, I definitely think you should check this one out! Sarah did a fantastic job with this, especially as her debut novel!

This book takes you on the journey of a detective who keeps hitting dead ends in a case of missing girls. In swoops the FBI, they believe they have a lead on who's taking these girls, and they want Katie to go undercover into a MC group that has ties to the DiAngelo mafia. Katie knew that this was going to be dangerous and she was going to have to be somebody completely different, but she wanted justice for the girls.

Katie, now turned Nicole, makes one heck of an entrance to get the attention of the MC and it definitely works. She meets Dalton and Maverick, the two brothers of the MC that are quite opposites of each other, but both draw her in immediately.

I love a good strong FMC, and this one delivered! There are emotions, suspense, spice, morally grey men, found family, and an FMC that is fighting the battle between her heart and her duty. The ending had a twist I wasn't expecting and then the epilogue tied it together so wonderful and almost had me crying (happy tears).

[Sw33tmidnight · Rating 5 out of 5]

OMG!
First this story pulled me in from the beginning! This was my first romantic suspense and it did not disappoint. As we go through the story we follow our FMC who is a detective! But she goes undercover for a case she's been working on for a while. After months of training she meets our 2 MMC's who are hot! And absolutely perfect in their own ways! One of them is hot and brooding talk about one who is always grumpy! The other is fun and sarcastic in his humorous ways! Talk about the best of both worlds! Did I mentions they are brothers! And very very possessive over our FMC even with each other! 🥵🥵 of course with the romance came the suspense and the suspense was spencing! As I was reading I would think I would know what was going to happen but never actually did! My heart was racing so much throughout this story! And the ending omg! If you don't read the ending through the epilogue well then you're wrong! Because that ending was amazing and beautiful and I am crying because of how perfect it was!
I highly suggest this read! But definitely check your content warnings!

[Deborah · Rating 4 out of 5]

Early in the book, I wondered what possessed me to pick up a MC novel. I'm just not usually a fan. This one was different, loads different. This was essentially a family who likes motorcycles, but likes saving people even more. The men respected their women, none of that "old lady" stuff except in jest.

The one thing that might have earned another star was better editing. The female protagonist is Katie, but the MC knows her as Nicky. But toward the end of the book, they call her Katie. A good editor would have caught that. Throughout the book, there are missing words and words that don't sync with the rest of the sentence. It might not matter to a lot of readers, but this former English teacher noticed and it threw my out of some crucial places in the story.

Otherwise, engaging characters, no glaring loose ends, a decent read. This author has potential.

I received an advance review copy for free, and I am leaving this review voluntarily.

[Karen GoatKeeper · Rating 4 out of 5]

Five young girls have disappeared without a trace. Officer Katie McGrady and her partner are at a dead end until she is offered a chance to go undercover as Nicole Moore with a biker gang. She takes it.
Except the gang isn't what the FBI tole her it was. Except the two brothers in charge break through her careful wall to keep this assignment only an assignment. Then most of the rest of the gang do the same.
Each step taking Nicky/Katie closer to solving the case takes her closer to the gang and to the deadly gang behind everything.
The book is a fast read. The story line is good. It does get a bit contrived in places and is predictable in others, but still makes fun reading.
One flaw is the graphic sex scenes. They are worked into the narrative well, but are really not needed in such detail. These read like juvenile fantasy sex encounters and break up the story.

[Nikki Church · Rating 5 out of 5]

I picked this up at a local bookstore where Sarah was signing Riding the Line. This book has elements I am interested in, and she's local, so why not give it a go? Make sure you read description/trigger warnings as it may include topics that are upsetting. (It is a why choose with a pair of brothers but no ⚔️.)

I loved it. Reading Katie/Nicky, Mac, and Dalton's story was a fun little ride. It had just enough suspense and romance as she infiltrates a motorcycle club to take down a trafficking ring. She quickly discovers things aren't what they seem and finds she enjoys the club and the friendships it provides. The epilogue is chef's kiss.

I cannot wait to get to read Jackson and Holly's story!

[Sandy Edwards · Rating 4 out of 5]

I just read Riding the Line, although this was not a typical read for me. The story summary captured my attention, so I decided to give it a try.
Detective Katie McGrady is asked to go undercover as Nicky Moore to infiltrate the Steel Saints Motorcycle Club with ties to the DiAngelos, a Mafia family. This is to hopefully solve a trafficking case she and her partner, Detective Shelly Vaughn have been working on. Katie is young, smart, and eager to learn, so she accepts.
Nicky infiltrates the Steel Saints MC and begins working at their clubhouse as a cook and cleaning person. Mac and Dalton Mills are brothers in the club, and the President is Silas Greyson who is not only scary but also a sleazeball. Nicky is attracted to both brothers and has a relationship with both.
I enjoyed the story, but there was too much sexual detail for my liking, particularly when it was with both Mac and Dalton. What I did like was how the club was like a family, and how Nicky became such good friends with two of the wives, Maria and Holly.
Will Nicky (aka Detective McGrady) take down the Steel Saints MC and the DiAngelos? If so, what happens to her relationships with all these people? Will she just walk away and return to the police force? You need to read this suspenseful story to find out what happens!
I received a copy of this book via BookSirens and my honest review is my own voluntary opinion.

[M W · Rating 3 out of 5]

Katie is a decorated cop that has been assigned to go undercover tonight filtration a mc club that could be involved with trafficking. 
Now Nicky she immediately catches the eye of 2 brothers who run the club Dalton and Mac. She starts falling in love with the club and the men and their family. She uncovers that they are not sho thr fbi think they are.
This book should have been a novella I think it would have flowed better. Some parts were a tad too rushed and I felt like we really didnt get much Dalton after the cabin. The authors note made me think it was not going to be a hea but dont fret. Love Holly and Maria alot.  I think this was rushed and slow in some parts made this not flow correctly. 

[Bookish_Ashleigh · Rating 5 out of 5]

This book was emotional, gripping, and beautifully written. The kind of story that lingers long after you finish. I fell in love with every single character, not just the main couple, but the entire unit, the family that made this world feel alive and real. It’s not just a romance; it’s a story about loyalty, love, and the unbreakable bonds that hold people together.
With suspense, heart, and raw emotion, Riding the Line delivered everything I want in a biker romance and I don’t even usually gravitate toward this trope. But this one? It’s top of my list now. Powerful characters, unforgettable relationships, and a ride that’s as emotional as it is exhilarating. 🖤🔥

[Cheryl Tabor · Rating 4 out of 5]

The story line needed to be more on the Thriller/Suspense side for me. There was absolutely too much spicy scenes that really took away from the body of the story line. Though there are true fine lines when going undercover. The Character building was great too. Had one believing true Motorcycle gang, and true cops. The ending was interesting. I enjoyed the take down of the bad guys. I would of given it a 5 if less criptic spice scenes. Just my preference. Others may like it as is. Thanks for the read.

[Racheal Marie · Rating 5 out of 5]

In every way possible, this novel was amazing. The author's note regarding mind triggers is located in the front. This narrative tracks Lieutenant Katie, often known as Nicky, as she goes on a routine undercover mission. Despite her lack of training and expertise, Katie was adamant about bringing those responsible for the female sex theft in her community to justice. You know what? Katie discovers that there are many shades of gray in life; it's not always black and white. There are some serious moments, as well as big surprises, conflicts, laughter, and spill-the-tea sessions.

[Amanda M · Rating 5 out of 5]

My first book by this author and it won't be my last. I was invested in this story once I started reading it. I loved the heroine she really was a strong, fearless character. And of course the morally gray heroes were amazing. Lots of suspense, plot twists, and romance. I thoroughly liked reading this. So, so good.


I received an advance review copy for free, and I am leaving this review voluntarily.

[Melanie · Rating 4 out of 5]

Absolutely loved this book. Katie became Nicky and found that she had always been Nicky. Dalton and Mac accepted her and all three formed a true family. The lies and deception finally came out but they all found that the love was stronger than the betrayal. I would have loved to give it 5 stars but there were so many little errors is the writing it needed better editing.

I received an advance review copy for free, and I am leaving this review voluntarily.

[Michelle Shamy · Rating 5 out of 5]

I LOVED this book! the FMC and burn MMC's were amazing in this book! this book was fast paced, with twists and turns. Katie aka Nikki went undercover. but never did she think she'd fall for two hot guys. The storyline in this was awesome. and i loved both Holly and Maria. this story had action, chaos, love. at some points my heart hurt.
I binged this book in less than 2 days. I'm ready for the next one already
❤️
thank you for allowing me to read this awesome book Sarah. I greatly appreciate it.

I received an advance review copy for free, and I am leaving this review voluntarily.

[Lisa Reynolds · Rating 5 out of 5]

I didnt want this book to end. First time I have ever wanted to be a part of a fictional family in a book! From the start the book pulls you in and it just picks up from there. Tons of chuckles, banter, sexy brothers, beautiful friends and the feeling of family. Katie, Mac, and Dalton just seemed to fit each other beautifully, growing stronger with every passing day. I can not wait for the second book to come out, its so far away!

Spice 🌶🌶🌶🌶

Touches on light dark topics

[Stacey Grammer · Rating 4 out of 5]

This book was everything I want in an MC romantic suspense — raw, dangerous, and unexpectedly emotional. The story is full of twists, loyalty, and found family, and the writing pulls you straight into the noise and chaos of that world. It’s equal parts heart-pounding and heart-aching, and by the end, I didn’t want to walk away.