What do you think?
Rate this book
Cerberus Tactical K9 Team Charlie #5
Acting on Instinct
When the world is on fire, the only way to survive is by Acting on Instinct.
Ty Newcomb, Tier One Delta Force operator and his tactical K9, Rory, are trained to move fast, strike hard, and complete the mission. Ty has built his life on control—and on secrets. Years ago, under CIA orders, he used psychological manipulation to win Kira’s heart. He followed the script, but the love that grew between them was real. Now he’s done with the world of shadows—and determined to show Kira she can trust what they feel is real.
Kira knows something is wrong. They tell her it’s PTSD—a lingering shadow from the terrorist attacks that nearly took her life. But her instincts say otherwise.
A cryptic warning arrives from halfway across the globe, pulling Kira into a fast-moving conspiracy tied to the international power elite and a man willing to destroy anything in his path—including his own family. Kira realizes she isn’t a survivor because the dangers aren’t in the past; she's still a target.
When Kira goes on the run to save her life, Ty and Rory move into action.
From Spain to Tanzania, Ty and Rory will cross continents to find Kira and destroy the threats that jeopardize their future together.
Escape into a high-stakes global chase where love and betrayal collide, featuring a battle-hardened protector, a brilliant heroine, and the unbreakable bond of a tactical K9 team. Acting On Instinct is a slow-burn, steamy but closed-door, action adventure romance packed with adrenaline, heart, and the power of found family.
Ty Newcomb, Tier One Delta Force operator and his tactical K9, Rory, are trained to move fast, strike hard, and complete the mission. Ty has built his life on control—and on secrets. Years ago, under CIA orders, he used psychological manipulation to win Kira’s heart. He followed the script, but the love that grew between them was real. Now he’s done with the world of shadows—and determined to show Kira she can trust what they feel is real.
Kira knows something is wrong. They tell her it’s PTSD—a lingering shadow from the terrorist attacks that nearly took her life. But her instincts say otherwise.
A cryptic warning arrives from halfway across the globe, pulling Kira into a fast-moving conspiracy tied to the international power elite and a man willing to destroy anything in his path—including his own family. Kira realizes she isn’t a survivor because the dangers aren’t in the past; she's still a target.
When Kira goes on the run to save her life, Ty and Rory move into action.
From Spain to Tanzania, Ty and Rory will cross continents to find Kira and destroy the threats that jeopardize their future together.
Escape into a high-stakes global chase where love and betrayal collide, featuring a battle-hardened protector, a brilliant heroine, and the unbreakable bond of a tactical K9 team. Acting On Instinct is a slow-burn, steamy but closed-door, action adventure romance packed with adrenaline, heart, and the power of found family.
281 pages, Kindle Edition
First published April 29, 2026
About the author
Fiona Quinn
84 books534 followersFiona Quinn is a USA Today bestselling author, a Kindle Scout winner, and an Amazon All-Star.
Quinn writes action-adventure romance in her Iniquus World of books including Lynx, Strike Force, Uncommon Enemies, Kate Hamilton Mysteries, FBI Joint Task Force, Cerberus Tactical K9 Team Alpha, and Delta Force Echo series.
She writes urban fantasy as Fiona Angelica Quinn for her Elemental Witches Series.
And, just for fun, she writes the Badge Bunny Booze Mystery Collection with her dear friend Tina Glasneck under the pen name Quinn Glasneck.
Canadian born, Fiona Quinn is now rooted in the Old Dominion where she lives with her husband. There, she pops chocolates, devours books, and taps continuously on her laptop.
Ratings & Reviews
Friends & Following
Create a free account to discover what your friends think of this book!
Community Reviews
Displaying 1 - 30 of 30 reviews
April 30, 2026
This book was filled with a lot of ups downs twist and turns that kept me on the edge of my seat While I was reading an arc copy of acting on instinct I fell in love would be ever growing love story between Kira and Tye And I really enjoyed getting to read Rory's last mission and how he was the 1 to save Ciara from under the bed on the plane And then get into his And then get into his retirement I loved the way the love story between Cara and Tye is so passionate but in more than a physical sense it's emotionally and almost as if they are spiritually connected it's just incredible to read each page Of every chapter was packed with an emotional rollercoaster that made you feel the emotions as if you were the 1 living through the story This was simply incredible Fiona Quinn outdid This was simply incredible Fiona outdid herself yet again and I cannot recommend this This was simply incredible Fiona Quinn outdid herself yet again and I cannot recommend this book enough And I hope to get Pete's into Rory's retirement through this ongoing Series I'm really looking forward to getting to know ninja and what she is capable of and seeing the adventures her and I go on along with the new members of this particular server's tactical team So this new branch of the series is going to be fantastic if this book is any indication I cannot read Recommend Fiona Quinn and her Branches that come off of it Enough Enough this book even though I received an ARC copy was my choice for the best book of April 2026 I have no doubt that if you choose to read this book in this entire series You will not be Disappointed Reading the entire The entire iniquit series from start to finish is a highly enjoyable read no matter how many times you read it and I love that Fiona keeps adding to the series making grow I love the entire little world created in this in Nicholas world And some of my favorite books from the iniquisaries is the service tactical canine units so I really look forward to reading more of those and I highly recommend you read them as well If I could give this book more than 5 stars I would It is 1 of my favorites by Fiona Quinn and that's saying a lot since I love all of her books but this is It is 1 of my favorites by Fiona Quinn and that's saying a lot since I love all of her books but this is indefinitely the top 5 spotindefinitely Out of her books
May 15, 2026
Loved this book! Ty & Rory make such a great team. Their love for Kira is unmatched. I love how the story had multiple characters with different adventures going on at once. It definitely kept me wanting more.
April 30, 2026
Ty wants to marry Kira
Kira is living in America to avoid her uncle making her marry someone in Qatar. Ty is called out on a mission when men come for Kira.
Kira is living in America to avoid her uncle making her marry someone in Qatar. Ty is called out on a mission when men come for Kira.
May 13, 2026
I've read all of the World of Iniqqus books and this is as good as any. After being used as an object for his own ends by her Uncle Nadir in Qatar, Kira, in the US, is still living in fear for her aunt Fatima, Nadir 's wife. This story returns to a previous book, where, for essential operational reasons, CIA agent Johnna White manipulated Ty and Kira to fall in love. Three years on, Nadir is more dangerous than ever and Fatima is in terrible danger. As usual in Fiona Quinn 's long series, there are times of breathtaking danger, super efficient operators - and since K9 operators have been involved, wonderful dogs. Rory especially, is a star.
It isn't absolutely necessary to read these books in order - in fact there are different lines of order. But however they're read, this book and all the others about special forces, their significant others and their dogs, are just fantastic! A thrill ride across the world
It isn't absolutely necessary to read these books in order - in fact there are different lines of order. But however they're read, this book and all the others about special forces, their significant others and their dogs, are just fantastic! A thrill ride across the world
April 30, 2026
This is the 5th book in this particular series, but characters from previous books often make a cameo or more major appearance in later books, and I love that! I’ve read all of the books in this series (along with probably 20 previous books by this fantastic author), but this book would stand alone well. I’m thrilled to read more of Ty and Kira’s love story and I enjoy the psychological techniques and information woven throughout the book. CIA and other alphabet agencies fascinate me, and I love reading about the military, special forces, K-9 units and private security. These books are great representations of the work these units do and they’re full of excitement and some romance. I can definitely recommend this sweet but sometimes heart-stopping story, the series, and anything by this author. I was provided an ARC, which I appreciate, but these opinions are my own.
May 23, 2026
Excellent Reading
Fiona Quinn is an amazing author. Very tactical, strategic, and psychological. Each aspect is thoroughly detailed. She doesn't get descriptive in the environment, as some authors. That's not a negative. When reading Quinn's writing, you are able to imagine the scene through broad strokes, but the detail is on the characters' actions, their thoughts, and emotions.
This story was tightly written in Quinn's manner. There is sex mentioned, but not explicity, it's "off screen." The reader can skip over it, or use their own imagination.
I highly recommend this book and this series. Please read the series in order. Check the author's website, Goodreads, fantastic fiction, or other web source for reading order.
Fiona Quinn is an amazing author. Very tactical, strategic, and psychological. Each aspect is thoroughly detailed. She doesn't get descriptive in the environment, as some authors. That's not a negative. When reading Quinn's writing, you are able to imagine the scene through broad strokes, but the detail is on the characters' actions, their thoughts, and emotions.
This story was tightly written in Quinn's manner. There is sex mentioned, but not explicity, it's "off screen." The reader can skip over it, or use their own imagination.
I highly recommend this book and this series. Please read the series in order. Check the author's website, Goodreads, fantastic fiction, or other web source for reading order.
April 30, 2026
The end of an era and the beginning of a new adventure!
We return to Ty and Kira's story....the fall out from White's original op where Ty and Kira first fell in love and the ripple effects of her family's interference in her life, politics, fuel supplies and so much more.
Ty's work is constantly pulling him away from Kira, Kira's family won't accept Ty or her choices, but surely love should conquer all? It will if Iniquus get their way! Lynx plays a huge part in this book along with Ty, Kira, White and Echo Team....so many favourites, all in one place! Multiple ops that cross in ways nobody expected and all have far reaching repercussions. As always a fantastic read on Kindle Unlimited.
We return to Ty and Kira's story....the fall out from White's original op where Ty and Kira first fell in love and the ripple effects of her family's interference in her life, politics, fuel supplies and so much more.
Ty's work is constantly pulling him away from Kira, Kira's family won't accept Ty or her choices, but surely love should conquer all? It will if Iniquus get their way! Lynx plays a huge part in this book along with Ty, Kira, White and Echo Team....so many favourites, all in one place! Multiple ops that cross in ways nobody expected and all have far reaching repercussions. As always a fantastic read on Kindle Unlimited.
May 7, 2026
how do you trust the tactical operator whose training and instincts let him shove you away from him in a moment of danger?
it's a gut thing. how dare he?
culturally and operationally, other males stood in front of her.
in an operation, they fought side by side.
what happens to your faith, trust and love and loyalty when he pushes you aside?
a visceral and intense blend of politics, romance and psy ops, with some amazing K9s and folks who might be at the heart of things, or who might end up collateral damage.
I really enjoy the unique blend of steamy, suspense and human and K9 connections and challenges.
it's a gut thing. how dare he?
culturally and operationally, other males stood in front of her.
in an operation, they fought side by side.
what happens to your faith, trust and love and loyalty when he pushes you aside?
a visceral and intense blend of politics, romance and psy ops, with some amazing K9s and folks who might be at the heart of things, or who might end up collateral damage.
I really enjoy the unique blend of steamy, suspense and human and K9 connections and challenges.
May 9, 2026
The over use of the word that
I usually really enjoy the story line of Fiona Quinn's books. But this time the over use of the word "that" was distracting. Most of the time the word could be left out and it would not detract from the flow of the sentence. Or it could be substituted with other words like the , it and of. I have noticed the overuse of the word that in other authors in the past couple of years.
The story was good but if the trend to over use the word that continues I will be looking for other authors to read.
I usually really enjoy the story line of Fiona Quinn's books. But this time the over use of the word "that" was distracting. Most of the time the word could be left out and it would not detract from the flow of the sentence. Or it could be substituted with other words like the , it and of. I have noticed the overuse of the word that in other authors in the past couple of years.
The story was good but if the trend to over use the word that continues I will be looking for other authors to read.
April 29, 2026
Fiona Quinn's books are always action-packed, with romance, intrigue, and danger. I love that Kira and Ty have more to their story. Of course, I LOVE Rory, the K9 Malinois. This book can be read as a standalone, but Fiona Quinn has a talented way of weaving the stories in and out of several books. Her books are best enjoyed if you read them in order. Her characters are always well thought out and relatable. I would give this series a 10 star!
May 15, 2026
military dogs & their handlers
Well as I am a dog lover, I love these stories of the these wonderful canines & their handlers. I have lived with & loved 8 dog wonderful dogs, 4 of them GSDs. And even tho I loved these dogs & I know they loved me, I can’t imagine the bond that develops between a MWD & their partner. Love these stories. Thank you
Well as I am a dog lover, I love these stories of the these wonderful canines & their handlers. I have lived with & loved 8 dog wonderful dogs, 4 of them GSDs. And even tho I loved these dogs & I know they loved me, I can’t imagine the bond that develops between a MWD & their partner. Love these stories. Thank you
May 17, 2026
Wow! Prepare yourselves to be wowed
This entire series has been one of the best. The action alone will keep the fascination going along with the comraderly between the team members along with their partners. This one though will bring your emotions to an all time high with tears included!
This entire series has been one of the best. The action alone will keep the fascination going along with the comraderly between the team members along with their partners. This one though will bring your emotions to an all time high with tears included!
July 1, 2026
Couldn’t put it down
This story kept me riveted from the first page. Revisiting the Iniquus teams, especially Lynx and Gator was a marvel. Spinning through the mystery, suspense and unknown through Kira’s eyes and perspective was brilliant. And Ty, as always was masterful, while real. Great book.
This story kept me riveted from the first page. Revisiting the Iniquus teams, especially Lynx and Gator was a marvel. Spinning through the mystery, suspense and unknown through Kira’s eyes and perspective was brilliant. And Ty, as always was masterful, while real. Great book.
April 29, 2026
Of course, five stars!!
I love And will read everything you ever write, and, I expect, on the day you release it. My favorites, however, are Lynx and Striker. Their books I've read more than once. :-D
I love And will read everything you ever write, and, I expect, on the day you release it. My favorites, however, are Lynx and Striker. Their books I've read more than once. :-D
April 30, 2026
Another excellent book!
Ty and Kira were great characters that we met in previous books along with Rory. Lots of action and suspense w with several characters from previous books involved. Loved it even if I lost some sleep to finish it!
Ty and Kira were great characters that we met in previous books along with Rory. Lots of action and suspense w with several characters from previous books involved. Loved it even if I lost some sleep to finish it!
May 3, 2026
I highly recommend reading Danger Signs by the same author before reading this book to get the most out of the story.
I’m not sure what words to use for a review so I’m just going to go do a quick reread. Perhaps then I will have the words to sum up this story.
I’m not sure what words to use for a review so I’m just going to go do a quick reread. Perhaps then I will have the words to sum up this story.
May 13, 2026
This book has wonderful characters along with the K-9s. I really love the K-9s, their work, their loyalty, their bravery, and the way they bond with their people. This story has a complex plot with lots of suspense, action, a romance, and it ends with a very happy ending.
May 14, 2026
Loved this! Thank you Fiona!
I’ve read everything that Fiona has written and have enjoyed all of them.
This story is a sweet bookend wrapping up the adventure from earlier books that featured the Zambia story line. Highly recommend!!
I’ve read everything that Fiona has written and have enjoyed all of them.
This story is a sweet bookend wrapping up the adventure from earlier books that featured the Zambia story line. Highly recommend!!
June 18, 2026
Will this group really get safely together
So this time the group had to figure out to rescue more than one person. And still they got it all done . But the best part was the very end with the changing of the dogs leads/ handlers.
So this time the group had to figure out to rescue more than one person. And still they got it all done . But the best part was the very end with the changing of the dogs leads/ handlers.
August 11, 2026
Love the mystique!
There are so many suspenseful plot twists in this story! Fiona creates a compelling masterpiece! You won’t be disappointed in any of this amazing storyteller’s books!
There are so many suspenseful plot twists in this story! Fiona creates a compelling masterpiece! You won’t be disappointed in any of this amazing storyteller’s books!
May 2, 2026
Excellent read!
I really enjoyed catching up with Kira, Ty and Rory. The pacing and suspense was very well done. Fiona Quinn has created a great series.
I really enjoyed catching up with Kira, Ty and Rory. The pacing and suspense was very well done. Fiona Quinn has created a great series.
May 4, 2026
Ok, this book was a continuation of the story in an earlier book. It wasn’t really about the K9 which was unfortunate, as that was the best part of the earlier books in the series.
May 5, 2026
Acting on Instinct
Fiona Quinn has done another incredible job of weaving a story filled with danger, suspense, outstanding characters, an amazing K9, and , of course, love.
Fiona Quinn has done another incredible job of weaving a story filled with danger, suspense, outstanding characters, an amazing K9, and , of course, love.
May 5, 2026
Can't wait for the next one to come out in this series of books 📚.
Great story she keeps you on your toes though out it.
Great story she keeps you on your toes though out it.
May 6, 2026
Loved..Loved!
I love all of Fiona Quinn’s books. Acting on Instinct was written with intelligence and empathy. It totally measured up.
I love all of Fiona Quinn’s books. Acting on Instinct was written with intelligence and empathy. It totally measured up.
May 6, 2026
Acting on Instinct book 5
Excellant book, especially Rory‼️
Anything with a MWD is so special.
Great writing and interactions with the characters.
Read the entire series.
Excellant book, especially Rory‼️
Anything with a MWD is so special.
Great writing and interactions with the characters.
Read the entire series.
May 8, 2026
So special
Kira finally got the love she sought. So special in the end with Rory getting to go home and Ninja joining the squad.
Kira finally got the love she sought. So special in the end with Rory getting to go home and Ninja joining the squad.
May 18, 2026
a quick read
All of these books follow the same general formula. That does not keep them from being an entertaining read. It’s good, but not essential, to read them in order.
All of these books follow the same general formula. That does not keep them from being an entertaining read. It’s good, but not essential, to read them in order.
May 23, 2026
❤️❤️❤️
May 27, 2026
Good book but I was expecting a Team Charlie book and IT IS NOT.
Displaying 1 - 30 of 30 reviews