As someone who usually enjoys police procedurals, I was intrigued by Head Cases and its premise: a serial killer targeting other serial killers, leaving a trail of grisly murders, riddles, and clues. The idea of a specialized FBI agent from the PAR (Patterns and Recognition) unit, who can see strange patterns and numbers, certainly had potential. However, the execution left me feeling a bit mixed.

The book features a lot of characters and numerous moving parts, which at times made the story hard to follow. The sheer number of people involved and the complexity of the case were a bit overwhelming, and I found myself struggling to keep track of who was who and how they connected to the plot.

While the beginning of the book was engaging, the second half felt like a slow burn, losing some of the momentum. I also had difficulty connecting with the characters, particularly the main character. Despite his unique abilities, I found myself not really caring for him, which made it hard to get fully invested in his journey. This lack of emotional connection left the story feeling less compelling. As for the plot itself, while it was intriguing, it didn’t feel particularly unique or fresh, and I found myself hoping for more twists or surprises that never quite materialized.

Overall, Head Cases had an interesting premise but didn’t fully capture my attention. It might appeal to those who enjoy a more complex, puzzle-like narrative, but the lack of connection to the main character made it harder for me to truly enjoy the book.

Thank you to the author, NetGalley & the publisher for my ARC in exchange for my honest review.

Well written and engaging police procedural book, reminiscent of Criminal Minds and Slow Horses.

The PAR (Patterns and Recognition) unit of the FBI consists of a group of misfits tasked with helping to solve cold cases. Gardner Camden has a very analytical brain but does not excel with social cues and interaction. They have heard that PAR is likely to be disbanded, and the news they just received doesn't help. Many years previously, Gardner helped to identify a serial killer who was presumed dead in a house fire. But he turns up murdered with many of the similar elements from his own kills. Then another serial killer is found dead. Gardner and his team need to find this culprit--and fast--using the clues the killer leaves behind.

I enjoyed this intriguing mystery, and the characters make it more interesting. There are a lot of moving pieces, a large number of characters, clues, elements, and details to keep straight. I listened to this as an audiobook and I liked how the narrator portrayed Gardner, helping me root for his success throughout.

The mystery itself is surprising and clues are revealed at the right times to keep the reader invested in discovering the outcome along with the characters. It's fast paced, with a good balance of action and suspense. I really hope this is the start to a series, because there are so many different directions and storylines this group of agents can pursue.

Being talked into buddy reads is one of my favorite pastimes! Mainly because if it’s good, we can rave about it together, and if we aren’t vibing with the book, we can bash the book together! 😝 In this case, we all really liked it!! It was hard to not fly through this one! I absolutely loved the unique cast of characters and learning about the PAR (patterns and recognition) unit of the FBI. It was fascinating to see them using their skills to track down a serial killer! This reads like a Criminal Minds type show! So if that’s your jam, I think you would enjoy this one too! Can’t wait to read more from this series

Enjoyed this listen and will be looking at this Authors other works. The story kept me interested and the narrator kept me wanting to listen. All in all it was a truly enjoyable time.

First and foremost, a large thank you to NetGalley, John McMahon, and Macmillan Audio for providing me with a copy of this publication, which allows me to provide you with an unbiased review.

Always looking for new and exciting authors, I discovered this book by John McMahon. This gritty story seeks to manage the serial killer theme by presenting a unique and mystifying group within the FBI who must chase them down. When a number of serial killers turn up dead, the FBI’s elite PAR Team is called to assist. Led by Gardner Camden, the team seeks to follow a killer and their vague clues across the country, while being goaded by this vigilante. Hoping to stem the violence and bring their newest killer to justice, Camden and the PAR will have to remain one step ahead of the ever-evolving situation. McMahon brings all the action in this piece, hoping to impress the reader from the outset.

Those who know Gardner Camden are familiar with his unique way of synthesising information. While many see his affinity for puzzles as somewhat autistic or a slice of savant, he gets things done and sees what others miss. He is the perfect fit for an elite unit within the FBI, where subtle is essential. The Patterns and Recognition (PAR) Team works well and is usually called in to assist when other groups have failed, which is perfect for Camden to lead.

After the murder of a long-thought-dead serial killer, PAR is called in on the sly. The group of five is used to cold cases, but this one is red hot, though the need for secrecy is key. Special Agent Camden must work all angles to discover the missing link and try to make sense of the recent discovery of a man he was sure had been dead. While trying to piece it all together, Camden must struggle with his ongoing issues trying to forge a relationship with his young daughter and estranged wife. They cannot understand his nuances or the importance he places in the job.

When the bodies of more serial killers turn up across the country, Camden and the rest of the team worries that this could be a vigilante killer who is trying to clean up the mess left by the Feds in the past. As rumours of the imminent disbanding of PAR, there is no room for error. When the killer begins taunting Camden and tries to send him subtle hints, the race is on to find someone who wants to show their mettle and keep the killings from being forgotten. Gardner Camden may have met his match, unless he can find the missing link. John McMahon delivers a great thrill with this piece and has me eager for more!

John McMahon does well with this thriller, keeping the reader on edge as much is revealed. The narrative introduces the reader to a great deal in short order pushing pieces together and providing strong pathways to guide things in a forward direction. As the momentum picks up, the reader is able to assemble things and keep the intensity, all while the story gets more twisted. Key characters provide some backstories as well as develop throughout the reading experience, never revealing too much at one time. This leaves the option open for more in the series, should McMahon wish to add other novels. The plot twists are constant and leave things in an ongoing mystery, though they are slowly exposed to keep the reader connecting as plot points emerge and truths surface. I can hope that John McMahon will return with another novel and use Gardner Camden to star in the leading role, as there is much about him that remains opaque and in need of exploration.

Kudos, Mr. McMahon, for this unique thriller that kept me hooked!

Truthfully, I don’t usually love books written in the POV of an investigator because they usually have too much unnecessary action, and that’s just not my jam; however, when I read the synopsis for Head Cases when perusing NetGalley for a new listen, this one intrigued me. Head Cases is a name for the FBI group, PAR (Pattern and Recognition) given by other FBI members to belittle the group. The members of PAR have screwed up at some point in their career and were sent to this group, usually to work on cold cases. Told in the POV of PAR leader, Gardner Camden, an extremely analytical and gifted investigator, the team gets assigned an old case of Gardner’s that was supposed to have been solved, but as it turns out, it was far from it with a serial killer on the loose killing other serial killers.

This book surprised me! It was giving much more Criminal Minds, with analyzing the suspects behaviors and tracking them based on patterns, and less 24 or the more action packed FBI themed media you tend to see, which is exactly what I want in a book like this! The mystery sucked you in from the jump! Hidden clues, dissecting behaviors to find the next move, and the cast of characters really kept this story moving at a great pace leaving you craving the resolution. I enjoyed this book much more than anticipated! My only complaint was, even though Gardner had a pretty solid back story, there was a couple forgotten plot points that I thought could have been touched on a bit more within his personal life to round him and the story out a little better.

Will Damron played every character so well and kept their voice unique. I loved his take on Gardner, keeping his voice rigid, flat, and professional - perfect for his personality.

Thank you, @macmillan.audio & @netgalley for allowing me to listen to this audiobook!

Within the world of the FBI sits a special unit called PAR: Patterns and Recognition, which is dubbed Head Cases by those outside the unit. Meant to be derogatory because the team consists of members who have “messed up” at some point during their time in the Bureau and relocated to this team. Still, they are all brilliant individuals and together they usually work on cold cases but in this instance there’s an active case they’re called in to solve, and it’s a doozy!

I absolutely devoured this book. It was one of those rare instances where I couldn’t wait to be back in these pages and found myself shirking responsibilities just so I could keep listening! Dark, twisty, and utterly addicting this clever story is one I won’t soon forget and I really REALLY hope this is the first in a series. I need more from these characters!

Thank you Macmillan Audio for the alc and Minotaur Books for the arc via Netgalley!

Pub day: January 28, 2025
Rating: 5/5⭐️

Thank you to NetGalley and MacMillan Audio for the gifted ALC.

I started this audiobook with no background on it aside from knowing it was about a serial killer. After listening to the first little bit, I had to push pause and see if it was based on a real story-that's how it felt-and it's not.

Gardner is our main POV who has a great memory, puzzle and code enthusiast, and quite the analytical brain-and he's often socially shorted. He is on the hunt to find what appears to be a reemerging of an old serial killer. The new kills are very similar from a number of connected cold cases. Can he find the culprit in time to save the next victim.

This was a good cat and mouse feel that also felt quite serious in nature. I liked the twists and connections that we were led to as the reader.

Thanks to NetGalley, MacMillan audio, and John McMahon for an ALC and chance to give my honest opinion!

Audiobook narration was 4.5 stars. Easy to follow, great character voices. I listened at 1.75x but 1.25x was a good conversational speed.

FBI misfits - "head cases" - are leading a case to catch a serial killer that seems to be killing. . . serial killers. An interesting take on a detective mystery book. I enjoyed the banter between the agents. A fun one for analytical minds as they unravel many puzzles and clues to solve the case. It really jumped right in from the gate with the hook. I did not find there were any "dull" moments as it flowed well and kept me interested throughout. I read that it will be made into a television series and I cannot wait to watch it!

Thanks to NetGalley and Macmillan Audio for an early release audiobook in exchange for an honest review.

4+ stars.

There is a group of brilliant misfits in a special unit at the FBI hunting serial killers. Agent Gardner Camden is the lead agent--he's brilliant at puzzles and has a photographic memory but his people skills are lacking. I liked Gardner and his team and I hope this becomes a series. Highly recommend.

I enjoyed Will Damron's narration.

Reminiscent of TV series criminal minds and Temperance Brennon series by Kathy Reichs this is another intriguing book that could be great book series or TV show with a neurodivergent main character. It felt like it was written to become a TV series. I would invest my time into a series with this character FBI Agent Gardner Camden who is neurodivergent and good with analytics and puzzles.

The mystery is a complex one and I loved guessing what was going to happen next and what the various clues might mean. The story is also faced paced due to the character rapport and dialogue / banter. Looking forward to more about from this author and main character.


I read the ebook and the audiobook in tandem - the narrator Will Damron of the book was really good and did an excellent job portraying the main character and the other minor characters voicing. The book was entertaining and kept be wanting more.


Thank you to Netgalley, Macmillan Audio and St. Martin's Press | Minotaur Books for this ARC/ LRC . This is my honest review.

Wow this is going to rank near the top for my favorite audiobooks of the year! First time author, Will Damron narrating, great title, and catchy cover all made this book one to be a highly recommended when it releases in January 2025. The plot was complex and detailed with unique and quirky characters. While this story was a lot of cat-and-mouse, it wasn’t my perfect type of chase.

I didn’t read the synopsis so while I am tempted to say what it’s about, I suggest you just skip it and read or listen to this page turning thriller!

Thank you to Netgalley and the publisher for the opportunity in exchange for an honest review.

FBI agents trying to find a serial killer (a Dexter or sorts) who is killing serial killers (or at least bad people). There is a leak in the agency. Who can FBI Agent Gardner Camden trust? He is an atypical thinking who sees strictly in right/wrong, which has hurt him in the past.

Enjoyable read. Kept me guessing. I listened to the audiobook and the narration was well done.

Thanks to MacMillan Audio & NatGalley for providing an audio ARC in exchange for an honest review.

I was really interested in the premise for this book - it sounded great, but it seems to be lacking in execution to me. I guess it's not *that* original - Slow Horses meets Criminal Minds - but brilliant + quirky + puzzles is catnip to me. Our MC is Gardner Camden, one of the more ridiculous names I've encountered; he is brilliant, quirky, and fond of puzzles, and he and his colleagues comprise the FBI's PAR Team (Patterns & Recognition). PAR is staffed with talented agents who have fucked up in the past, but we only get the full breakdown of Gardner's own transgression, which is that he turned in his wife, who is also the daughter of his longtime partner, for cooking the books of a business with her boss. This causes her to go to prison, and Gardner's partner, Saul, to have a fatal heart attack, and causes Gardner to be relegated to desk jockey rather than field agent, before being recruited to PAR.

PAR's role seems conflicted, as we are frequently told it's an amazing, super-effective unit that tackles hard cases and succeeds, yet its existence is always in jeopardy. It's a small detail, but it annoyed me.

PAR is called in to investigate the murder of a murderer who was thought to have died in a fire 7 years previous. Apparently he faked his death at that time, extracting two of his own molars and putting them in the sacrificial corpse's mouth (HOW did no one notice this?); the current dead body is missing those molars. Mutilations to his corpse are the same as in his MO for the murders of young women he was suspected of committing, leading the team to deduce it's a vigilante killing, a real life Dexter (although Miami's favorite son is not mentioned - darn!). Later, the presumed killer calls Gardner to taunt him (but does he also feel a kinship with the FBI?). Thus begins a cross-country chase as the killer targets additional murderers in various circumstances; one is killed in an FBI safe house, leading the team to suspect someone with ties to the Bureau.

The plot is fine, the action is good; the flying back and forth across the country is a little much and seems near to physically impossible for even the most energetic of psychopathic killers. Where things fall apart is Gardner's inner workings: we are clearly meant to feel a kinship with him, and feel for his personal troubles. Unfortunately, he is coded as high-functioning autistic, and his ability to process emotions in a way that is relatable is ... not great. At least as written by this author (I can think of plenty of autistic characters who have moved me emotionally; Christopher Boone from <i>The Curious Incident of the Dog in the Night-time</i> comes to mind, but Gardner is tough to connect to).

I can see where this would be an entertaining teleplay, and I read that it has been optioned for HBO, so there's that.

Will Damron does a fine enough job with the voice acting. I was mostly able to differentiate between characters. He's got a little bit of a radio announcer thing going on, but it was fine.

3 stars

I really enjoyed this and that has been rare for me this year. This was an intricately plotted story about how the FBI catches a serial killer. Specifically part of the FBI called PAR, where problematic and aging agents are placed. The team is assigned to capture a serial killer that hunts other killers, leading to a decades long mystery.

This is a really good thriller that I hope more people check out. I was absolutely enraptured by the audiobook. It also featured in large part my city which was awesome.

Thank you Macmillan Audio and netgalley for giving me an advanced review copy of this audiobook in exchange for an honest review.

I really enjoyed the narration in this book.

I don't usually love police procedurals, but this had more of a feel of a full TV that I would follow. It has the great makings to be a series.

You really felt connected to the characters and the FBI agent that was investigating the case.

I loved this book! it was clever, it was dark and highly addictive. And come on serial killers, it had me there to be fair!! I really do hope this is the start of a new series, I want more of these characters, they were so interesting and have so much more to tell us .

The Patterns and Recognition team at the FBI are hunting a killer, a killer who is killing serial killers, it is pretty graphic at times, as you would expect from this storyline. The team are all super intelligent and I loved every bit of it. Getting inside the killers head through the team putting all the puzzle pieces together was very satisfying

The narrator, Will Damron was fantastic as always. He always brings the story to life.

Thanks so much to Macmillan Audio for my early copy of the audiobook to listen to . Out on January 28th, a must read for crime enthusiasts.

(4.25 stars)
Head Cases is the derogatory nickname other FBI folks give the members of a special unit called PAR: Patterns And Recognition. They are people who have messed up in some way in other FBI posts but they each are brilliant in their own way and seem to work really well together, usually working on cold cases.

This time, though, they are called in for a “hot” case. They are assigned to find a serial killer who is out there killing other serial killers! Gardner Camden leads the team for the first time, and he is grappling with this responsibility in addition to working the case. I loved his character; we get to know him professionally and personally. His love for his young daughter was palpable. The other members of the team were written as individuals so I had no trouble keeping track of who was who.

The mystery is a complex one and I loved guessing what was going to happen next and what the various clues might mean. The audiobook kept me and my husband entertained on a long road trip. The narrator did a fabulous job with all the voices. I’m going to look for more books narrated by Will Damron!

I sure hope there are going to be more books featuring these characters. The ending certainly hinted at it. In the meantime, I’m going to try to read his earlier books.

Thank you to Macmillan Audio and NetGalley for the opportunity to listen to an advance copy of this audiobook and St. Martin’s Press and NetGalley for the opportunity to read an advance reader copy of this book. All opinions are my own.

Real talk, I have severe insomnia (ugh, fun times), and this book was totally my overnight BFF. I binged it hard in one sitting, and let me just say, it was a wild ride. Think puzzles, FBI drama, and a whole lot of mind games that kept me turning pages like my life depended on it.

The characters? Oh, they were quirky for sure, and I low-key loved the whole misfit team vibe. The stakes felt real, like the team genuinely couldn’t afford to mess up. Also, the lead agent, is a brilliant mess—just the kind of character I love. His mind works in a way that made me want to keep reading more and more to see how he'd piece things together. The clues and riddles kept me on my toes, wondering what would happen next.

But, of course, not gonna lie, some parts had me squinting like, “Wait, what?” but overall, the twists were solid, and the story kept me hooked. It felt like an intense mix of smarts and chaos, and honestly, I was here for it.

This hit differently, maybe because I was so in the mood for a binge-worthy escape. If you're into thrillers with brainy, flawed characters and just a sprinkle of dark justice, give this one a go.

Big thanks to NetGalley for the ARC in exchange for my honest opinion! 🌟🌟🌟🌟

"Head Cases" is an exhilarating debut novel that follows a team of FBI agents, led by Gardner Camden, as they pursue a serial killer determined to impose his own brand of justice. With the team on the brink of disbandment, Camden and his colleagues must decipher a trail of cryptic riddles and clues left by the killer, racing against time to prevent further victims. The novel delves into themes of justice, vengeance, and the complexities of morality as the team faces an increasingly twisted and personal plot.

From the start, I was completely hooked, and it was hard to believe this was a debut. The author’s ability to blend suspense with intricate character development made the story even more compelling. Gardner Camden, the protagonist, is a well-rounded character—intelligent, complex, and haunted by personal struggles that add significant depth to the narrative.

One of the most striking aspects of the book is its realistic portrayal of an ongoing investigation. The meticulous attention to detail allows the reader to feel as if they’re part of the case. Every clue, every twist, contributes to the sense that the serial killer is always one step ahead, but the team's intelligence and determination keep them on track toward solving the mystery.

Overall, "Head Cases" is a fast-paced, thrilling read that skillfully balances suspense with emotional depth. I’m eager to see what the author has in store for future books, as this debut shows immense promise.