Unchecked: Renegade Force

Detective Remy Ferguson Thriller Mystery Series #4

by Dan Grylles

Two police officers are killed during a mysterious hit. Crime is allowed to flourish, for a price. And a bomber is terrorizing Miami.

A renegade force spreads its dominion throughout Miami and exerts its destructive power, unchecked .

Unchecked is the first installment in the Renegade Force trilogy in the Det. Remy Ferguson Thriller Mystery Series. Before he ever encounters L'Inconnu in Book 1 of the series, a younger Sgt. Remy confronts corruption and conspiracy that is entangling the city in a shadowy web of fear and danger.

This is the story of how Remy Ferguson earns the right to be called Miami's Best Detective.

Follow Remy as his challenge unfolds over the next three books in the the Renegade Force trilogy today with Unchecked!

Genres: Thriller

367 pages, Kindle Edition

Published July 20, 2025

About the author

Dan Grylles is an award winning short story author. At a young age he developed three lifelong passions - writing computer programs, writing music to play on his guitar, and reading mystery/crime novels. Later, lured by the intrigue of thriller mysteries, he followed the clues of his own life and began writing those too. Dan's professional background includes many years managing a pet sitting business which inspired his fun and quirky novella, M is for Dog Show. Contact: Dan@DanGrylles.com.

Reviews

[Tara Leigh · Rating 5 out of 5]

An explosive prequel to the L’Inconnu series, Unchecked: Renegade Force takes readers deep into the chaos of a maniacal bomber targeting police. The tension is high, the pace is relentless, and the stakes are wildly intense.

It’s a thrill to watch Remy evolve into the detective we’ve come to admire in later books. And a special shoutout to Marmalade the cat, the unsung hero who, may or may not, actually save the day.

Dan Grylles proves once again why he's one of my absolute favorite authors. If you love:

• 💥 Mind-blowing twists
• 🚔 Police procedurals
• 📚 Prequels that add depth to beloved characters
• ⚡️ Fast-paced, impossible-to-put-down reads

…this one needs to be on your shelf.

[Roger Campbell · Rating 5 out of 5]

📚 Book Review by R.M. Campbell 📚
Unchecked: Renegade Force
By
Dan Grylles

⭐⭐⭐⭐⭐


This is book 4 in the Detective Remington (Remy) Ferguson Thriller Mystery Series, although it’s the first installment of the Renegade Force trilogy. This story begins with a younger Sgt. Ferguson and showcases his climb to become Miami’s Best Detective. Sgt. Remy is assigned to a mysterious bombing that kills two police officers and a civilian. Questions began to mount as to who the target was, the police on the scene, or the civilian killed in the explosion. With very little evidence to go on, no witnesses, and a mysterious motive, Remy is hard pressed in his effort to investigate the bombing. When another bombing occurs involving the police, and they can track down a witness, a pattern starts to evolve, involving corruption and conspiracy in his own backyard. Remy and his team pull out all the stops to find the bomber and solve the case before he kills again.
I enjoyed reading this thrilling mystery. The plot was well-written, and the pace was easy to follow. The characters were well developed, and their interactions were engrossing. There was ample suspense and tension to keep the reader captivated, wanting to read more. A hint of romance was also a nice touch, added to enhance the overall reading experience and highlight the human element of the story. The book was action-packed, with unexpected twists that intensified the overall enjoyment of the story. I recommend this book to anyone looking for a good thriller-mystery to devour.

[Micki · Rating 4 out of 5]

When I started this book, I didn't realize it was a part of series, and greatly appreciated that I was able to enjoy it without any prior knowledge from the other books. The story quickly pulls you into the action, where we find the main character, Detective Remy Ferguson working at the scene of an “explosion” that turns out to be the first in a series of bombings. The author then introduces new characters (with varying motives) which keeps the reader guessing as to who the bomber might be. His female characters (a police officer, a district attorney, and a reporter) are all strong and well developed, which I really appreciated. The resolution was well thought out and well told. I found myself feeling some empathy for the “bad guy” as their whole backstory was revealed. I can see how some of the characters and events could be woven into previous and subsequent books in the series. Overall, a great read and I’m very tempted to read the entire series.

[Laurel Whitney · Rating 4 out of 5]

Dan Grylles’ Unchecked Renegade Force is book #4 in the series, but it’s the first book of his I’ve read. I was able to read it and I didn't feel like I missed anything by not knowing the back story from his previous books. (The only exception to that would be the use of initials for police jargon, most of which I was able to figure out.) This is a thrilling mystery, lots of twists - - some of which I solved, but enough to hold my attention throughout.

Remington “Remy” Ferguson is a great police detective solving crimes in the crime-riddled Miami-Dade district of Florida. He is trying to stop a clever, knowledgeable bomber who seems to have a vendetta against the police department. The clues are evident - - or are they?

There’s even a sneak peek at the next book in the series which makes me want to read more to solve this puzzle.

[Laura R · Rating 5 out of 5]

This book can be read as a stand alone as Unchecked takes us back to early in Remy's career as a Detective. The main focus of this book is a bomber who seems to have a grudge against law enforcement. In addition, we get a glimpse into Remy's personal life and there is a secondary plot of some cops who appear to be involved in less than legal activities.

I loved the intertwining of the storylines, the twists as the story progressed, and the mix of characters. While working the case, Remy comes across some information which causes him to play his cards close to his vest. And even his cat, Marmalade, plays a key role at one point. The ending has left me anticipating what could be in store for Remy next given the hints at the end of this story and I look forward to reading it.

[Francis Nantha · Rating 5 out of 5]

This novel works well on its own without expecting a reader to be familiar with the others within the series - being an origin story despite it's #4 sequencing.

From the get-go, this is a fast-paced narrative that presents multiple perspectives - allowing the reader to be a step ahead of the protagonist chasing after a taunting serial killer.

Without spoilers, the plotting is enough of a page-turner that you may want to binge-read till the end rather than spreading it over a few days.

Without any background of the series earlier, thinking this was a standalone book, the cliffhanger ending was a tad irritating - but it definitely made me search for more details and I will be looking to read the rest of this series.

[Becca · Rating 5 out of 5]

I could NOT put this down. I absolutely love Remy and crew. This was a hard one. Because like Gabby, the lines blur. Because of situations, you want to root for the guy doing the harm, even though he's doing harm. Especially when you find out his story. I was honestly suspicious of her a bit as well. Still kind of am. This kept you guessing. It could go one way, then in an instant, another path was formed. It's definitely a fly by the seat of your pants thrill ride. And after seeing the first two chapters of the next one.....it's going to be just as good. I highly recommend this series. You don't necessarily have to read them in order, but personally, I think you should. Certain things make more sense. Great series to get started on!

[Sarah Between the Lines Book Reviews · Rating 5 out of 5]

Fast paced, thrilling ride and action packed.
Thoroughly enjoyed this read, definitely easy to read within a day, just set aside those responsibilities, they will be there when you finish this book!

It is book 4 in the series, however, this was the first one I read and didn't feel like I missed any critical info from the previous 3 books.

[Gloria · Rating 5 out of 5]

This is book 4 about Detective Remy Ferguson of the Miami Police Department. We go back to the beginning of his career to see how he earned his stellar reputation. Someone is targeting and killing Miami cops some who may be involved in illegal drugs. Remy is put in charge of the case. Great story.

I received a free copy of this book via Booksprout and am voluntarily leaving a review.

[Nora Flood-Houston · Rating 5 out of 5]

Another amazing book in this series. Detective Remy Ferguson is a good cop. He has an innate ability to put the pieces together on a case. Who is blowing up Miami? Again he figures out the missing link. Sad that he found someone to date only for it to end before it actually began. A must read!.

I received a free copy of this book via Booksprout and am voluntarily leaving a review.

[Barbara Harrison · Rating 5 out of 5]

Allow two days for this intense, contemporary, laugh-out-loud, bomb-investigation procedural mystery thriller set in Miami, Florida, in June. It involves abduction, dirty cops, drugs, motorcycles, murder, PTSD, rescue, and attempted romance.

I received a free copy of this book via Booksprout and am voluntarily leaving a review.

[Debbie Jones Warren · Rating 5 out of 5]

Here is yet another incredibly-written thriller from Dan Grylles. Like the others in the series, this one has terrific twists and turns. A gripping read!

[Texas · Rating 5 out of 5]

Detective Remy Ferguson Thriller Mystery Series:
UNCHECKED, #4 - A rather complex read with interesting characters and intriguing story lines set at a constant pace making for an immersing read. Just as you thought the story was complete, there was more in the woodwork. Well done. Source: Booksprout. 5*

DRAGGING DOWN, #0 - A simplistic, quickly read novella introducing Ferguson with an interesting twist in a case he is investigating. Source: BookSprout. 4*

MYSTERY OF L'INCONNU, #1 - A more indepth killing spree. It drug on in the beginning but became more interesting as the story unfolded. Good story lines with a variety of characters, and plenty of misdirection to keep my interest. A bit wordy but a still entertaining. There is the L'Inconnu Passenger Manifest describing the passengers, which did not interest me. I wanted to read L'Inconnu fresh without knowing anything about the passengers. Source: Booksprout. 4*

INNOCENCE LOST, #2 - A faster pace than 'Mystery of L'Inconnu' and filled with a lot of intrigue making for an interesting story. Bad news though, the multiple investigations are not finished making the story just stop point blank, to be continued. Source: BookSprout. 4*

MASS INFLICTION, #3 - Interesting and intriguing, although the start was slow. Once the story picked up it was immersing with good story lines, plenty of misdirection (some obvious), and some surprises. Not as good as Innocence Lost, but still a good read. 4*
Detective Remy Ferguson Thriller Mystery Series end.