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Lethal Design: A Crime Thriller
392 pages, Kindle Edition
Published August 4, 2026
About the author
S.F. Baumgartner
22 books502 followersS.F. Baumgartner crafts fast-paced Christian suspense thrillers, weaving tales of complex characters, secretive operatives, and relentless agents. Her gripping storytelling has earned acclaim, with Living Secrets—Book 1 of her Mirror Estate series—named a Top Pick in the thriller category at Killer Nashville, 2024. When she’s not plotting her next twist, she’s binge-watching crime TV shows, like NCIS or playing with her cats. Fans of James Patterson's style, especially those who appreciate short, punchy chapters, will find much to love in her work.
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Displaying 1 - 30 of 85 reviews
August 6, 2026
Unraveling the Pattern: A High-Stakes Procedural Thriller
S.F. Baumgartner delivers another fast-paced, high-stakes crime thriller in Lethal Design, the compelling second installment of the KC & Orlando Prime Series.
It has been a year since the tragic and seemingly random murder of Linda Peters—a cold case that continues to haunt her husband, Frank. However, when a new federal initiative uncovers a chilling pattern connecting several deaths, Frank finds himself tied directly to the heart of the investigation. Barred from leading the case due to his personal connection, Frank turns to Investigator Kylie Cassidy (KC) of the Orlando Police Department, calling on her proven investigative instincts and sharp skills to spearhead the effort.
What follows is an intense, multi-agency collaboration bringing together Orlando Prime, KC, her partner Spaulding, and federal task forces. As jurisdictions overlap and secrets unfold, the team must race against time to unravel the mastermind and the true motive behind the killings.
Baumgartner excels at crafting intricate procedural details, high-level federal tension, and complex dynamics between local law enforcement and federal agencies. The plot moves at a relentless speed, keeping readers guessing while highlighting KC’s unique talent for connecting pieces others miss.
A fantastic follow-up for fans of police procedurals, procedural crime fiction, and multi-layered mystery series.
I received an advance review copy for free, and I am leaving this review voluntarily.
S.F. Baumgartner delivers another fast-paced, high-stakes crime thriller in Lethal Design, the compelling second installment of the KC & Orlando Prime Series.
It has been a year since the tragic and seemingly random murder of Linda Peters—a cold case that continues to haunt her husband, Frank. However, when a new federal initiative uncovers a chilling pattern connecting several deaths, Frank finds himself tied directly to the heart of the investigation. Barred from leading the case due to his personal connection, Frank turns to Investigator Kylie Cassidy (KC) of the Orlando Police Department, calling on her proven investigative instincts and sharp skills to spearhead the effort.
What follows is an intense, multi-agency collaboration bringing together Orlando Prime, KC, her partner Spaulding, and federal task forces. As jurisdictions overlap and secrets unfold, the team must race against time to unravel the mastermind and the true motive behind the killings.
Baumgartner excels at crafting intricate procedural details, high-level federal tension, and complex dynamics between local law enforcement and federal agencies. The plot moves at a relentless speed, keeping readers guessing while highlighting KC’s unique talent for connecting pieces others miss.
A fantastic follow-up for fans of police procedurals, procedural crime fiction, and multi-layered mystery series.
I received an advance review copy for free, and I am leaving this review voluntarily.
August 5, 2026
It’s very important to understand that Shadowed Secret and Lethal Design are connected, so I would recommend reading that too.
Lethal Design is basically about The Architect (case that was left behind for KC to solve). The Chameleon however was a closed case in shadowed secrets.
The starting might confuse you as Frank has a huge team and getting to know everyone takes time. The storyline is outstanding (once you dive into it, you’ll understand why). The characters are so nicely developed with strong personalities and motives. Everything is great about this book. I simply love detective Kylie Cassidy.
Lethal Design is basically about The Architect (case that was left behind for KC to solve). The Chameleon however was a closed case in shadowed secrets.
The starting might confuse you as Frank has a huge team and getting to know everyone takes time. The storyline is outstanding (once you dive into it, you’ll understand why). The characters are so nicely developed with strong personalities and motives. Everything is great about this book. I simply love detective Kylie Cassidy.
August 5, 2026
Fast paced, mess with your mind kind of thriller. You have staged scenes, a strange phrase, unlikely cod and some very determined investigators who want to find the thread that connects it all and will lead to a perpetrator. This is a wild ride. I got hooked from the start and just didn’t want to stop reading. Great pacing, some very good surprise twists to keep you guessing and some great characters to root for as they dig into this perplexing case. If you like thrillers give this one a go!.
I received a free copy of this book via Booksprout and am voluntarily leaving a review.
I received a free copy of this book via Booksprout and am voluntarily leaving a review.
July 24, 2026
Received this from bookSirens as an ARC
This is my honest review.
Lethal Design was an engaging mystery thriller that kept me turning the pages from beginning to end. I really enjoyed the way the story unfolded, with enough twists to keep me guessing without becoming confusing.
The characters were interesting, and the pacing kept me wanting to read “just one more chapter.” Having now read another book by S.F. Baumgartner, I can honestly say I’m becoming a fan of the author’s writing style and look forward to reading more.
If you enjoy well-paced mysteries with intriguing characters and plenty of suspense, I’d definitely recommend giving this one a try.
This is my honest review.
Lethal Design was an engaging mystery thriller that kept me turning the pages from beginning to end. I really enjoyed the way the story unfolded, with enough twists to keep me guessing without becoming confusing.
The characters were interesting, and the pacing kept me wanting to read “just one more chapter.” Having now read another book by S.F. Baumgartner, I can honestly say I’m becoming a fan of the author’s writing style and look forward to reading more.
If you enjoy well-paced mysteries with intriguing characters and plenty of suspense, I’d definitely recommend giving this one a try.
August 10, 2026
Lethal Design by S.F. Baumgartner is a Crime Thriller with Christian elements. It is the second book in the KC & Orlando Prime series.
What if the perfect murder looked like an accident?
That’s the chilling question at the heart of Lethal Design, a pulse-pounding crime thriller that grabbed my attention from the very first page and never let go. Packed with clever twists, relentless suspense, and an investigation that grows darker with every clue, this is the kind of book that keeps you saying, “Just one more chapter!”
When what appears to be another routine death lands on investigators’ desks, most people are ready to move on. But Kylie “KC” Cassidy isn’t convinced. She recognizes unsettling similarities to a case from the past, and her instincts tell her something far more sinister is unfolding.
As KC and the Orlando Prime task force begin connecting the dots, they uncover a terrifying pattern. Successful professionals with no history of addiction are dying under nearly identical circumstances. These aren’t random tragedies—these are carefully orchestrated deaths, designed by someone brilliant, patient, and always one step ahead.
I loved how the mystery unfolded piece by piece. Every new clue raised more questions, and every breakthrough revealed another shocking layer of deception. Just when I thought I had figured out who was behind it all, the story took another unexpected turn. The suspense never lets up, making it nearly impossible to put the book down.
KC Cassidy is exactly the kind of heroine I enjoy following—smart, determined, and unwilling to ignore the details everyone else overlooks. Her dedication to uncovering the truth, even when the danger becomes personal, makes her both relatable and admirable. The members of the Orlando Prime task force complement one another well, creating a team dynamic that adds depth and authenticity to the investigation.
What really sets Lethal Design apart is its intelligent storytelling. Instead of relying on graphic violence, the author creates edge-of-your-seat tension through meticulous detective work, psychological suspense, and a villain whose methods are as chilling as they are ingenious. Every chapter raises the stakes, leaving you wondering who will become the next target—and whether KC can stop the killer before it’s too late.
If you’re a fan of Terri Blackstock, Lynette Eason, Criminal Minds, or NCIS, you’ll feel right at home in these pages. The story delivers everything I love in a clean suspense novel: compelling characters, an intricate mystery, unexpected twists, and a satisfying conclusion that leaves you eager for the next installment.
Lethal Design is an outstanding launch to the Orlando Prime series and one I highly recommend to anyone who enjoys smart, fast-paced crime thrillers with memorable characters and plenty of surprises. If this first case is any indication, KC Cassidy and the Orlando Prime team have many exciting investigations ahead—and I’ll definitely be following along.
⭐⭐⭐⭐⭐ 5/5 Stars
Have you read Lethal Design yet? Did you solve the mystery before KC did, or did the twists catch you completely by surprise? Let me know in the comments—I always love hearing from fellow thriller fans!
So if you enjoy crime thrillers with Christian elements, check out Lethal Design by S.F. Baumgartner and the rest of the KC & Orlando Prime series.
I received a complimentary copy of this book, but this in no way influenced my review. All opinions are my own.
What if the perfect murder looked like an accident?
That’s the chilling question at the heart of Lethal Design, a pulse-pounding crime thriller that grabbed my attention from the very first page and never let go. Packed with clever twists, relentless suspense, and an investigation that grows darker with every clue, this is the kind of book that keeps you saying, “Just one more chapter!”
When what appears to be another routine death lands on investigators’ desks, most people are ready to move on. But Kylie “KC” Cassidy isn’t convinced. She recognizes unsettling similarities to a case from the past, and her instincts tell her something far more sinister is unfolding.
As KC and the Orlando Prime task force begin connecting the dots, they uncover a terrifying pattern. Successful professionals with no history of addiction are dying under nearly identical circumstances. These aren’t random tragedies—these are carefully orchestrated deaths, designed by someone brilliant, patient, and always one step ahead.
I loved how the mystery unfolded piece by piece. Every new clue raised more questions, and every breakthrough revealed another shocking layer of deception. Just when I thought I had figured out who was behind it all, the story took another unexpected turn. The suspense never lets up, making it nearly impossible to put the book down.
KC Cassidy is exactly the kind of heroine I enjoy following—smart, determined, and unwilling to ignore the details everyone else overlooks. Her dedication to uncovering the truth, even when the danger becomes personal, makes her both relatable and admirable. The members of the Orlando Prime task force complement one another well, creating a team dynamic that adds depth and authenticity to the investigation.
What really sets Lethal Design apart is its intelligent storytelling. Instead of relying on graphic violence, the author creates edge-of-your-seat tension through meticulous detective work, psychological suspense, and a villain whose methods are as chilling as they are ingenious. Every chapter raises the stakes, leaving you wondering who will become the next target—and whether KC can stop the killer before it’s too late.
If you’re a fan of Terri Blackstock, Lynette Eason, Criminal Minds, or NCIS, you’ll feel right at home in these pages. The story delivers everything I love in a clean suspense novel: compelling characters, an intricate mystery, unexpected twists, and a satisfying conclusion that leaves you eager for the next installment.
Lethal Design is an outstanding launch to the Orlando Prime series and one I highly recommend to anyone who enjoys smart, fast-paced crime thrillers with memorable characters and plenty of surprises. If this first case is any indication, KC Cassidy and the Orlando Prime team have many exciting investigations ahead—and I’ll definitely be following along.
⭐⭐⭐⭐⭐ 5/5 Stars
Have you read Lethal Design yet? Did you solve the mystery before KC did, or did the twists catch you completely by surprise? Let me know in the comments—I always love hearing from fellow thriller fans!
So if you enjoy crime thrillers with Christian elements, check out Lethal Design by S.F. Baumgartner and the rest of the KC & Orlando Prime series.
I received a complimentary copy of this book, but this in no way influenced my review. All opinions are my own.
August 13, 2026
KC Cassidy and Orlando Prime are at it again in S.F. Baumgartner’s latest release and second installment in Ms. Baumgartner’s KC & Orlando Prime series, Lethal Design! Lethal Design centers on Commander Frank Travers, the leader of the Orlando Prime Task Force, as he enlists the help of Detective KC Cassidy from the Orlando PD to help solve the murder of his wife, Linda. As KC and her partner, Detective Rick Spaulding, dig into Linda Travers’ case file, they learn it may be linked to other cases, but nothing is as it seems. Things seem off…and even staged. Even as Orlando Prime is working their own cases, the cases seem to be intertwined with what KC and Spaulding are working on. Orlando Prime comes to the same conclusion: Things seem off…and even staged. As KC and Orlando Prime work together, and yet separately, the answer to their collective cases may have been staring them in the face all along.
I loved being immersed into the world that S.F. Baumgartner created in Lethal Design! The way Ms. Baumgartner wrote Lethal Design gave me vibes of CSI: Miami and Hawaii Five-O! I was pleasantly surprised that Ms. Baumgartner had Commander Frank Travers take more of a center role than the previous book I read from the series. The way Ms. Baumgartner wrote Travers, I felt like Travers was solely focused on making sure his Wife’s case was solved before he allowed himself to grieve. I love that Lethal Design flipped back and forth between what KC was working on and what Orlando Prime was working on. I just wished that Lethal Design had more Faith present in the story, but that is more of a personal preference and by no means took away from me enjoying the book. I thought the title Lethal Design was very fitting for what the story was about and the things that transpired between the pages. Lethal Design had its suspenseful moments, but I was desperately wanting more moments that would leave me on the edge of my seat and sadly it didn’t. I still was able to find enjoyable moments and I was extremely happy that Commander Travers could make steps to move forward in his life. Lethal Design also left me with questions: Are we sure it’s over? And why doesn’t Orlando Prime hire KC already and make her a part of the team? I really can’t wait to see what S.F. Baumgartner creates next to see if any of my questions get answered and to see what KC and Orlando Prime are up to next! I highly recommend Lethal Design by S.F. Baumgartner!
Have you read Lethal Design? What did you think of the book?
I would like to thank the Publisher, NetGalley, and Celebrate Lit Blogging Tours for giving me a copy of Lethal Design to review, for letting me be a part of the Lethal Design Celebration Tour, and for providing the information needed for this post. All thoughts and opinions are my own.
I loved being immersed into the world that S.F. Baumgartner created in Lethal Design! The way Ms. Baumgartner wrote Lethal Design gave me vibes of CSI: Miami and Hawaii Five-O! I was pleasantly surprised that Ms. Baumgartner had Commander Frank Travers take more of a center role than the previous book I read from the series. The way Ms. Baumgartner wrote Travers, I felt like Travers was solely focused on making sure his Wife’s case was solved before he allowed himself to grieve. I love that Lethal Design flipped back and forth between what KC was working on and what Orlando Prime was working on. I just wished that Lethal Design had more Faith present in the story, but that is more of a personal preference and by no means took away from me enjoying the book. I thought the title Lethal Design was very fitting for what the story was about and the things that transpired between the pages. Lethal Design had its suspenseful moments, but I was desperately wanting more moments that would leave me on the edge of my seat and sadly it didn’t. I still was able to find enjoyable moments and I was extremely happy that Commander Travers could make steps to move forward in his life. Lethal Design also left me with questions: Are we sure it’s over? And why doesn’t Orlando Prime hire KC already and make her a part of the team? I really can’t wait to see what S.F. Baumgartner creates next to see if any of my questions get answered and to see what KC and Orlando Prime are up to next! I highly recommend Lethal Design by S.F. Baumgartner!
Have you read Lethal Design? What did you think of the book?
I would like to thank the Publisher, NetGalley, and Celebrate Lit Blogging Tours for giving me a copy of Lethal Design to review, for letting me be a part of the Lethal Design Celebration Tour, and for providing the information needed for this post. All thoughts and opinions are my own.
August 11, 2026
Lethal Design, the second installment of S.F. Baumgartner's KC & Orlando Prime series, the author once again proves her mastery of high-stakes investigative suspense. Building on the foundation of her Mirror Estate universe, this novel weaves a complex, multi-agency narrative that balances intricate procedure with deeply personal stakes.
What stands out most is Baumgartner’s meticulous attention to authentic law enforcement operations—whether detailing the friction between various federal agencies or mapping out complex field tactics. She delivers a wealth of technical context without ever overwhelming the reader or stalling the plot’s momentum.
At the emotional core of the story is Commander Frank Travers, whose world is shattered following the murder of his wife, Linda. When two separate team investigations begin to converge, Frank finds himself pursuing a ruthless killer connected to past events in the Mirror Estate series (specifically Stolen Secrets). The story elevates simple procedural drama into a high-octane chase as the investigators realize this perpetrator is merely one node in a far larger, more dangerous network. Yet, despite the killer's seemingly flawless history, cracks in the design begin to show.
Beyond the sharp writing and intricate plotting, the narrative is grounded by quiet, meaningful threads of faith that add depth to the characters as they navigate severe tragedy and injustice.
Intelligent, thrilling, and satisfyingly complex, Lethal Design is a outstanding addition to Baumgartner’s expanding universe. It is a must-read for fans of procedural thrillers, and it leaves no doubt that both the KC & Orlando Prime and Mirror Estate series have plenty of compelling ground left to cover.
What stands out most is Baumgartner’s meticulous attention to authentic law enforcement operations—whether detailing the friction between various federal agencies or mapping out complex field tactics. She delivers a wealth of technical context without ever overwhelming the reader or stalling the plot’s momentum.
At the emotional core of the story is Commander Frank Travers, whose world is shattered following the murder of his wife, Linda. When two separate team investigations begin to converge, Frank finds himself pursuing a ruthless killer connected to past events in the Mirror Estate series (specifically Stolen Secrets). The story elevates simple procedural drama into a high-octane chase as the investigators realize this perpetrator is merely one node in a far larger, more dangerous network. Yet, despite the killer's seemingly flawless history, cracks in the design begin to show.
Beyond the sharp writing and intricate plotting, the narrative is grounded by quiet, meaningful threads of faith that add depth to the characters as they navigate severe tragedy and injustice.
Intelligent, thrilling, and satisfyingly complex, Lethal Design is a outstanding addition to Baumgartner’s expanding universe. It is a must-read for fans of procedural thrillers, and it leaves no doubt that both the KC & Orlando Prime and Mirror Estate series have plenty of compelling ground left to cover.
August 4, 2026
Lethal Design is a gripping crime thriller that hooks you from the very first chapter and refuses to let go. Instead of relying on nonstop action, S.F. Baumgartner carefully builds tension through layered investigations, intelligent detectives, and mysteries that connect in unexpected ways.
The story begins with Commander Frank Travers, who is still haunted by the brutal murder of his wife, Linda, a psychologist whose killer was never found. Just before dying, Linda leaves behind a cryptic message written in her own blood: "No suicide confutatis m." A year later, Frank discovers that her death may be connected to a string of suspicious cases including staged suicides, opioid overdose deaths, and a mysterious underground cult linked to the Latin phrase Confutatis Maledictis.
One of the novel's biggest strengths is its pacing. Every clue feels meaningful, and the author avoids unnecessary filler. The investigative process is detailed without becoming overwhelming, making readers feel like they are solving the case alongside the detectives.
The writing is clean and cinematic, making it easy to visualize each crime scene and interrogation. The suspense builds steadily rather than relying on cheap twists, and the multiple storylines keep the pages turning.
Overall, Lethal Design is an excellent choice for readers who enjoy crime fiction, psychological suspense, and intricate detective mysteries.I would highly recommend it to fans of investigative thrillers and look forward to seeing how the larger mystery unfolds in the rest of the series.
The story begins with Commander Frank Travers, who is still haunted by the brutal murder of his wife, Linda, a psychologist whose killer was never found. Just before dying, Linda leaves behind a cryptic message written in her own blood: "No suicide confutatis m." A year later, Frank discovers that her death may be connected to a string of suspicious cases including staged suicides, opioid overdose deaths, and a mysterious underground cult linked to the Latin phrase Confutatis Maledictis.
One of the novel's biggest strengths is its pacing. Every clue feels meaningful, and the author avoids unnecessary filler. The investigative process is detailed without becoming overwhelming, making readers feel like they are solving the case alongside the detectives.
The writing is clean and cinematic, making it easy to visualize each crime scene and interrogation. The suspense builds steadily rather than relying on cheap twists, and the multiple storylines keep the pages turning.
Overall, Lethal Design is an excellent choice for readers who enjoy crime fiction, psychological suspense, and intricate detective mysteries.I would highly recommend it to fans of investigative thrillers and look forward to seeing how the larger mystery unfolds in the rest of the series.
August 11, 2026
In Lethal Design, S.F. Baumgartner delivers a tight, fast-paced procedural thriller that grabs hold from the opening pages and doesn't let go. The story picks up a year after the tragic death of Commander Frank Travers's wife, Linda, who was found alongside a chilling phrase written in her own blood: "no suicide confutatis m'." When a string of apparent opioid overdoses begins surfacing with the exact same cryptic message, Frank tasks Detective Kylie "KC" Cassidy with investigating the suspicious death of TJ Simms. Despite scene staging that suggests suicide, none of the victims have a history of drug use—and Simms happens to share a work address with Frank's late wife. What unfolds is a high-stakes game of cat-and-mouse as the Orlando Prime team races to unmask a calculated serial killer. Baumgartner excels at character development, building seamlessly on the groundwork laid in Fatal Invitation. Returning readers will appreciate the deepening character dynamics, though new readers can easily dive in and enjoy the mystery on its own merits. The narrative maintains relentless momentum, driving toward a tense confrontation. While the resolution leaves a few fascinating threads dangling—and leaves you demanding ultimate justice for the perpetrator—it sets the stage perfectly for what promises to be an explosive next chapter. Smart, gripping, and expertly paced, Lethal Design is a stellar entry in the series that will keep crime fiction fans eagerly anticipating the next installment.
August 10, 2026
S.F. Baumgartner delivers a masterclass in suspense with Lethal Design, a gripping mystery that pulls you in from the opening page and refuses to let go.
What elevates this novel is its seamless balance of intricate plotting and authentic character depth. The protagonist’s sharp intuition and complex motivations anchor the narrative, while the surrounding cast—from deceptive allies to calculating figures in the shadows—keeps the psychological tension perpetually high. Baumgartner crafts every plot turn with precision; the twists are clever and unexpected without ever feeling unearned or confusing.
The narrative pacing is relentless, effortlessly creating that "just one more chapter" momentum that defines the best thrillers in the genre. Having experienced Baumgartner’s distinct storytelling style across multiple books, it is clear this is an author who knows exactly how to build atmosphere and keep readers guessing until the final reveal.
Verdict:
If you enjoy an expertly paced mystery rich in suspense, sharp character dynamics, and unpredictable turns, Lethal Design is a must-read.
What elevates this novel is its seamless balance of intricate plotting and authentic character depth. The protagonist’s sharp intuition and complex motivations anchor the narrative, while the surrounding cast—from deceptive allies to calculating figures in the shadows—keeps the psychological tension perpetually high. Baumgartner crafts every plot turn with precision; the twists are clever and unexpected without ever feeling unearned or confusing.
The narrative pacing is relentless, effortlessly creating that "just one more chapter" momentum that defines the best thrillers in the genre. Having experienced Baumgartner’s distinct storytelling style across multiple books, it is clear this is an author who knows exactly how to build atmosphere and keep readers guessing until the final reveal.
Verdict:
If you enjoy an expertly paced mystery rich in suspense, sharp character dynamics, and unpredictable turns, Lethal Design is a must-read.
August 5, 2026
⭐️⭐️⭐️⭐️
This was a gripping crime thriller that had me hooked from the very first chapter. What begins as a seemingly routine death soon unfolds into a much larger and more intricate mystery, making it difficult to put the book down.
I really enjoyed following KC and the Orlando Prime task force as they uncovered the connections between a series of suspicious deaths. The investigation was well-paced, with each new discovery adding another layer to the mystery. The suspense builds steadily, and the twists kept me guessing until the very end.
The writing is clear, engaging, and easy to follow, making the story flow effortlessly. I also appreciated the strong investigative focus and the way the author gradually revealed the bigger picture without giving too much away too soon.
This is an absorbing and intelligently plotted thriller with memorable characters, plenty of suspense, and a satisfying conclusion. It's a great choice for readers who enjoy crime fiction, police procedurals, and mysteries that keep you thinking long after you've turned the final page.
This was a gripping crime thriller that had me hooked from the very first chapter. What begins as a seemingly routine death soon unfolds into a much larger and more intricate mystery, making it difficult to put the book down.
I really enjoyed following KC and the Orlando Prime task force as they uncovered the connections between a series of suspicious deaths. The investigation was well-paced, with each new discovery adding another layer to the mystery. The suspense builds steadily, and the twists kept me guessing until the very end.
The writing is clear, engaging, and easy to follow, making the story flow effortlessly. I also appreciated the strong investigative focus and the way the author gradually revealed the bigger picture without giving too much away too soon.
This is an absorbing and intelligently plotted thriller with memorable characters, plenty of suspense, and a satisfying conclusion. It's a great choice for readers who enjoy crime fiction, police procedurals, and mysteries that keep you thinking long after you've turned the final page.
August 5, 2026
Some designs were never meant to be uncovered...
If you love a high-stakes, meticulously plotted mystery, this book needs to be on your TBR list immediately.
The premise hooks you from the start: what looks like routine, tragic deaths across the city are actually the work of an invisible, patient mastermind engineering outcomes for victims with no history of addiction. Enter KC, a character whose sharp instincts and personal connection to a past event drive the investigation forward.
The story moves at a fantastic pace as the Orlando Prime task force follows separate, seemingly unrelated leads that gradually converge into a single, dark center. The author does a brilliant job building atmosphere, tension, and a genuine sense of danger. As the truth begins to unravel, the stakes skyrocket, making it nearly impossible to put down.
A thrilling, smart, and gripping read for anyone who enjoys clever police procedurals, conspiracy thrillers, or psychological suspense. Highly recommended!
If you love a high-stakes, meticulously plotted mystery, this book needs to be on your TBR list immediately.
The premise hooks you from the start: what looks like routine, tragic deaths across the city are actually the work of an invisible, patient mastermind engineering outcomes for victims with no history of addiction. Enter KC, a character whose sharp instincts and personal connection to a past event drive the investigation forward.
The story moves at a fantastic pace as the Orlando Prime task force follows separate, seemingly unrelated leads that gradually converge into a single, dark center. The author does a brilliant job building atmosphere, tension, and a genuine sense of danger. As the truth begins to unravel, the stakes skyrocket, making it nearly impossible to put down.
A thrilling, smart, and gripping read for anyone who enjoys clever police procedurals, conspiracy thrillers, or psychological suspense. Highly recommended!
August 11, 2026
Lethal Design is a well-paced and intriguing crime thriller that builds suspense through a complicated investigation. Detective KC finds herself looking into a series of unusual deaths that initially appear unrelated, but as she examines the evidence more closely, certain details begin to raise serious questions. The investigation becomes increasingly challenging as KC tries to understand what connects the cases and who could be responsible.
I particularly enjoyed KC’s character and her approach to solving the case. She is intelligent, observant, and persistent, always willing to look deeper instead of accepting the obvious explanation. The mystery unfolds gradually, with new information adding another layer to the story and keeping the outcome uncertain. I also liked that the suspense comes largely from the investigation, clues, and psychological elements rather than graphic details.
The story does a good job of maintaining curiosity throughout, and several unexpected developments kept me interested in seeing where the investigation would lead.
I particularly enjoyed KC’s character and her approach to solving the case. She is intelligent, observant, and persistent, always willing to look deeper instead of accepting the obvious explanation. The mystery unfolds gradually, with new information adding another layer to the story and keeping the outcome uncertain. I also liked that the suspense comes largely from the investigation, clues, and psychological elements rather than graphic details.
The story does a good job of maintaining curiosity throughout, and several unexpected developments kept me interested in seeing where the investigation would lead.
August 11, 2026
5/5 Stars
Lethal Design by S. F. Baumgartner is a well-written crime thriller that combines suspense, mystery, and Christian elements in a way that keeps the story engaging from beginning to end. KC is a strong and determined protagonist, and I enjoyed following her as she worked through the case and tried to uncover the truth. The Orlando Prime team also adds depth to the story, with each character bringing something different to the investigation. Their teamwork and dedication made the case even more interesting to follow. The mystery unfolds at a steady pace, with enough twists and unexpected moments to keep me guessing. I also appreciated that the story focuses on the investigation without becoming overly graphic, making it an easy and enjoyable read for fans of clean crime fiction. Lethal Design is a strong beginning to the Orlando Prime series. KC Cassidy is a memorable character, and I’m looking forward to seeing what future cases bring for her and the team. A great choice for readers who enjoy clean, character-driven crime thrillers with plenty of mystery and suspense.
Lethal Design by S. F. Baumgartner is a well-written crime thriller that combines suspense, mystery, and Christian elements in a way that keeps the story engaging from beginning to end. KC is a strong and determined protagonist, and I enjoyed following her as she worked through the case and tried to uncover the truth. The Orlando Prime team also adds depth to the story, with each character bringing something different to the investigation. Their teamwork and dedication made the case even more interesting to follow. The mystery unfolds at a steady pace, with enough twists and unexpected moments to keep me guessing. I also appreciated that the story focuses on the investigation without becoming overly graphic, making it an easy and enjoyable read for fans of clean crime fiction. Lethal Design is a strong beginning to the Orlando Prime series. KC Cassidy is a memorable character, and I’m looking forward to seeing what future cases bring for her and the team. A great choice for readers who enjoy clean, character-driven crime thrillers with plenty of mystery and suspense.
August 4, 2026
Lethal Design is about Commander Frank Travers whose wife Linda was murdered a year earlier Frank is still looking for answers when his team starts investigating the strange deaths of several successful people who seem to have no reason to die from drug overdoses. One case involves T J Simms whose death is made to look like an overdose and suicide. Detective Kylie KC Cassidy notices things that do not seem right, and the investigation slowly reveals that these deaths may be connected.
I really enjoyed reading Lethal Design because it has mystery, crime, and suspense. I liked how the small clues slowly helped the characters understand the bigger mystery
The story kept me curious because I wanted to know who was responsible and how all the cases were connected I also liked the characters and how they worked together to find the truth. Overall I found the book interesting and exciting and I would recommend it to anyone who enjoys crime and mystery stories.
I really enjoyed reading Lethal Design because it has mystery, crime, and suspense. I liked how the small clues slowly helped the characters understand the bigger mystery
The story kept me curious because I wanted to know who was responsible and how all the cases were connected I also liked the characters and how they worked together to find the truth. Overall I found the book interesting and exciting and I would recommend it to anyone who enjoys crime and mystery stories.
August 10, 2026
This was an engaging and fast-paced mystery that kept me interested from beginning to end. The story takes readers into a complicated investigation where seemingly unrelated deaths slowly begin to reveal a much bigger and more disturbing picture.
KC stands out as a strong and capable investigator, and I enjoyed watching her work through the clues and uncover connections that others had overlooked. The involvement of multiple law enforcement agencies adds another layer of tension, especially as the investigation becomes more complex and the truth starts coming to light.
I particularly enjoyed the investigative aspect of the story. The procedural details felt well-developed without making the book difficult to follow, and the steady flow of new information kept me curious about what would happen next.
This is a gripping crime mystery with a strong investigative lead, plenty of suspense, and an intriguing case that keeps you turning the pages.
KC stands out as a strong and capable investigator, and I enjoyed watching her work through the clues and uncover connections that others had overlooked. The involvement of multiple law enforcement agencies adds another layer of tension, especially as the investigation becomes more complex and the truth starts coming to light.
I particularly enjoyed the investigative aspect of the story. The procedural details felt well-developed without making the book difficult to follow, and the steady flow of new information kept me curious about what would happen next.
This is a gripping crime mystery with a strong investigative lead, plenty of suspense, and an intriguing case that keeps you turning the pages.
August 10, 2026
Lethal Design is a gripping crime mystery that combines suspense, investigation, and plenty of unanswered questions. Frank Travers is still searching for answers after the tragic death of his wife, Linda, and a mysterious clue she leaves behind gives the case a new direction.
Detective Cassidy brings a strong investigative presence to the story. I enjoyed watching her work through the evidence and slowly uncover connections that suggest Linda’s murder may be part of something much larger. Frank’s personal connection to the case also adds an emotional element to the investigation.
The story does a good job of revealing information gradually, keeping the mystery interesting without becoming difficult to follow. The unexpected turns and developing clues kept me curious about who was responsible and how everything would come together.
Lethal Design is an engaging and easy-to-follow mystery with memorable characters, suspense and enough twists to keep you turning the pages.
Detective Cassidy brings a strong investigative presence to the story. I enjoyed watching her work through the evidence and slowly uncover connections that suggest Linda’s murder may be part of something much larger. Frank’s personal connection to the case also adds an emotional element to the investigation.
The story does a good job of revealing information gradually, keeping the mystery interesting without becoming difficult to follow. The unexpected turns and developing clues kept me curious about who was responsible and how everything would come together.
Lethal Design is an engaging and easy-to-follow mystery with memorable characters, suspense and enough twists to keep you turning the pages.
August 10, 2026
I really enjoyed this crime mystery. What stood out to me was how the story brings together several investigations and slowly shows that they may not be as unrelated as they first appear.
KC is a particularly interesting character. She is observant, determined, and willing to look beyond the obvious, which makes her investigation enjoyable to follow. I also liked the way the different agencies and investigators contributed to the bigger picture.
There are plenty of suspicious deaths and unusual details throughout the story, and I found myself constantly wondering how they were connected. The mystery unfolds gradually, giving the reader enough clues to stay involved without making everything too predictable.
This was a well-paced and engaging crime read with realistic characters and an intriguing case. I would definitely recommend it to readers who enjoy mysteries that focus on investigation, clues, and uncovering the truth.
KC is a particularly interesting character. She is observant, determined, and willing to look beyond the obvious, which makes her investigation enjoyable to follow. I also liked the way the different agencies and investigators contributed to the bigger picture.
There are plenty of suspicious deaths and unusual details throughout the story, and I found myself constantly wondering how they were connected. The mystery unfolds gradually, giving the reader enough clues to stay involved without making everything too predictable.
This was a well-paced and engaging crime read with realistic characters and an intriguing case. I would definitely recommend it to readers who enjoy mysteries that focus on investigation, clues, and uncovering the truth.
August 11, 2026
S.F. Baumgartner delivers an adrenaline-fueled crime novel in Lethal Design that grips you from the opening scene and never lets up.
The story drops you right into the middle of a baffling investigation filled with staged crime scenes, cryptic phrases, and unusual causes of death. At the center of the storm are Frank Travers and Detective Kylie Cassidy, two determined leads whose relentless pursuit of the truth drives the entire narrative. As they fight to find the single thread connecting these perplexing events to a hidden perpetrator, their dynamic creates an irresistible blend of grit, heart, and sharp detective work that gives readers characters to truly root for.
Baumgartner excels at psychological warfare, constantly shifting the floor beneath your feet with clever, unpredictable twists. The pacing is razor-sharp, turning a complex web of clues into a seamless, addictively readable experience.
The story drops you right into the middle of a baffling investigation filled with staged crime scenes, cryptic phrases, and unusual causes of death. At the center of the storm are Frank Travers and Detective Kylie Cassidy, two determined leads whose relentless pursuit of the truth drives the entire narrative. As they fight to find the single thread connecting these perplexing events to a hidden perpetrator, their dynamic creates an irresistible blend of grit, heart, and sharp detective work that gives readers characters to truly root for.
Baumgartner excels at psychological warfare, constantly shifting the floor beneath your feet with clever, unpredictable twists. The pacing is razor-sharp, turning a complex web of clues into a seamless, addictively readable experience.
August 4, 2026
Lethal Design is a gripping crime thriller that kept me hooked from beginning to end. The story follows Commander Frank Travers, who is still searching for answers after the tragic murder of his wife, Linda. As he teams up with Detective KC Cassidy to investigate a series of mysterious deaths, they uncover clues that suggest these cases may all be connected.
I really enjoyed how the mystery unfolded step by step. The author built suspense in a way that kept me guessing, and every new clue made the story even more intriguing. The characters felt realistic, and the twists kept me excited to see what would happen next.
Overall, this was an engaging and well-written mystery with plenty of suspense and unexpected moments. If you enjoy crime thrillers with clever investigations and surprising twists, I would definitely recommend Lethal Design
⭐⭐⭐⭐⭐
I really enjoyed how the mystery unfolded step by step. The author built suspense in a way that kept me guessing, and every new clue made the story even more intriguing. The characters felt realistic, and the twists kept me excited to see what would happen next.
Overall, this was an engaging and well-written mystery with plenty of suspense and unexpected moments. If you enjoy crime thrillers with clever investigations and surprising twists, I would definitely recommend Lethal Design
⭐⭐⭐⭐⭐
August 10, 2026
Lethal Design is an engaging crime mystery with a good balance of suspense and investigation. Frank Travers is still struggling with the loss of his wife, Linda, whose murder remains unsolved. When a mysterious message she left behind comes into focus, it gives Frank and Detective KC Cassidy a new direction to follow.
I enjoyed KC’s approach to the investigation and the way she carefully puts the clues together. As she and Frank dig deeper, they begin to uncover connections between Linda’s death and other unusual cases, making the mystery more complicated with every discovery.
The story keeps the suspense steady and reveals information at just the right pace. I liked the gradual uncovering of secrets and the way the investigation kept raising new questions. It’s a straightforward and intriguing mystery with interesting characters and enough twists to keep you reading.
I enjoyed KC’s approach to the investigation and the way she carefully puts the clues together. As she and Frank dig deeper, they begin to uncover connections between Linda’s death and other unusual cases, making the mystery more complicated with every discovery.
The story keeps the suspense steady and reveals information at just the right pace. I liked the gradual uncovering of secrets and the way the investigation kept raising new questions. It’s a straightforward and intriguing mystery with interesting characters and enough twists to keep you reading.
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August 20, 2026After finishing the first book in this series, I couldn't wait to get my hands on Lethal Design. Thankfully, it was absolutely worth the wait. S.F. Baumgartner has a way of writing suspense that completely pulls me in, and before I knew it, I'd lost track of time because I was so invested in figuring out what was really happening.
This book is packed with tension, action, and mystery. I honestly had to make myself slow down because it would have been so easy to read the whole thing in one sitting. The investigation felt smart and well-crafted, and the twists kept me guessing until the end. If you enjoy crime thrillers that keep your brain working while your heart is racing, this series is one I'd definitely recommend.
I received a complimentary copy of this book. Opinions expressed in this review are completely my own.
This book is packed with tension, action, and mystery. I honestly had to make myself slow down because it would have been so easy to read the whole thing in one sitting. The investigation felt smart and well-crafted, and the twists kept me guessing until the end. If you enjoy crime thrillers that keep your brain working while your heart is racing, this series is one I'd definitely recommend.
I received a complimentary copy of this book. Opinions expressed in this review are completely my own.
August 4, 2026
Lethal Design is book 2 after Fatal Invitation. Fatal Invitation was the first book that I read about detective Kylie Cassidy and honestly I loved it. Part 2 was even better—my only suggestion is to read book 1 & 2 together because reading both of them after several months might cause you some character remembrance problems. I remembered Kozlov but didn’t remember the Orlando prime team so it took me some time to get comfortable with the characters. Other than that it’s amazing. Starts off with Frank and then proceeds with Frank taking KC’s help to solve Linda’s murder. The scenes are smoothly executed and chapters are short + fast paced. Great storyline and I look forward to more work by the same author. Highly recommended.
August 11, 2026
The long awaited Book 2, KC & Orlando Prime crime thriller is FINALLY here!
Released on August 4th, the absolute cleverness of the story, and how it intersected with the author's other book series' just blew me away! Not that you need to have read the other books - but you will definitely want to go and immerse yourself in these stories after this experience!
Detective Kylie Cassidy has good instincts and tenacity, she combines her street smarts and cop smarts as she pairs up with her Major Crimes partner, Detective Spaulding. Together they work to unravel a collection of tenuously linked overdoses.... or are they staged murders. This leads them to work in parallel with Damon Cruz and Claire Santos of Orlando Prime, where the pieces of an unsolvable cold case start to come together...
Will they all get in each other's way, or find a a way to pull together before the cover ups get deeper....
Released on August 4th, the absolute cleverness of the story, and how it intersected with the author's other book series' just blew me away! Not that you need to have read the other books - but you will definitely want to go and immerse yourself in these stories after this experience!
Detective Kylie Cassidy has good instincts and tenacity, she combines her street smarts and cop smarts as she pairs up with her Major Crimes partner, Detective Spaulding. Together they work to unravel a collection of tenuously linked overdoses.... or are they staged murders. This leads them to work in parallel with Damon Cruz and Claire Santos of Orlando Prime, where the pieces of an unsolvable cold case start to come together...
Will they all get in each other's way, or find a a way to pull together before the cover ups get deeper....
August 15, 2026
Lethal Design is another excellent thriller by S. F. Baumgartner. I always enjoy the way she combines the work of multiple agencies to get the job done. The writing is tight and provides an unrelenting feeling of tension. The different points of view between the "bad guy", the police department, and Orlando Prime provide a constant feeling of movement in the story and keep the reader fully engaged. As usual with Ms. Baumgartner's work, once I started the book, I resented anything that got in my way and required I put it down. Which only meant that I got back to it as quickly as possible. I highly recommend this series for detective fans of all types. I received a review copy from the author via BookSirens, and this review reflects my honest and voluntary opinion.
August 4, 2026
Lethal Design is an interesting and suspenseful crime mystery. The story begins after Frank Travers loses his wife, Linda, in a murder that remains unsolved. Before dying, Linda leaves behind a strange message, which becomes an important clue. As Frank and Detective KC Cassidy investigate, they discover that Linda’s case may be connected to other mysterious deaths.
I enjoyed how the story slowly revealed new secrets and made me curious about who was behind the crimes. The characters were interesting, and the mystery kept me wanting to read more.
It was an exciting book with suspense, mystery, and unexpected twists.
I enjoyed how the story slowly revealed new secrets and made me curious about who was behind the crimes. The characters were interesting, and the mystery kept me wanting to read more.
It was an exciting book with suspense, mystery, and unexpected twists.
August 10, 2026
As the name says it, the book was lethal and super engaging. The only reason why I rated it 4/5 is because there were parts that got me confused and I couldn’t grasp the plot because there was this overlapping thing. Other than that it’s truly action packed from the beginning to the end. There’s so much going on that you tell yourself just one more chapter. This time there’s double fun as there Orlando Prime and task force working simultaneously and there’s also an interesting twist that KC is trying to solve the case that was left as a cliffhanger in book 7 of the mirror estate series. Okay sorry about this spoiler but I had to.
August 2, 2026
I kind of get lost, I can’t keep up with the names or the characters, but if a novel or a thriller has a lot of suspense, I love it nevertheless. Lethal design is such a novel. Apparently there is a murderer, who kills and/or stages murders, and there are detectives and inspectors and police officers, and, I guess, also intelligence service agents involved, who try to solve the case. It’s fast-paced, well written, it’s a thriller, and I really enjoyed reading it. I did not quite understand the ending, but that’s on me. I’d, thus, recommend this book, which was made available to me in a pre-publication version by NetGalley in exchange for an honest review.
August 2, 2026
This book was very good! The way that S.F. Baumgartner keeps up with so many different aspects of the story is just amazing. It was gripping from the very beginning and she slowly unraveled things to keep my full attention at all times. Each character is so complex but done so well you can’t help but really like each one. This book is definitely worth reading and if you have not read the two before this one, that is a must!
“I voluntarily reviewed a complimentary copy of this book which I received from the author. All views expressed are only my honest opinion.”
“I voluntarily reviewed a complimentary copy of this book which I received from the author. All views expressed are only my honest opinion.”
August 4, 2026
Lethal Design is an exciting crime thriller full of mystery and suspense. Detective KC Cassidy and Commander Frank Travers work together to solve a series of dangerous crimes. Linda, Frank's late wife, plays an important role because her death is connected to the investigation. The story has interesting characters and unexpected twists that keep the reader engaged. Overall, it is an enjoyable book for fans of crime and mystery stories.
Althoug a great appriciation for the author highly recommend 👌
Althoug a great appriciation for the author highly recommend 👌
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