This book was a little rough to start with. I wasn't super engaged until about 40% into the book, but then, I couldn't put it down.

It's not meant for the squeamish, as a serial murder mystery, there are some gory descriptions. This book was intelligently written book that focuses on a quirky unit of the FBI full of wounded and gifted individuals and how they work through an unpredictable case. I can often kind of figure out murder mysteries pretty easily, but this was well written and developed so I couldn't predict until the very end.

A specialty group of FBI agents that are put together for their unique talents to create a rag-tag team who focuses on the patterns of crimes. Garnder Camden is the leader of this group and takes his team through some brutal killings that hit close to home. A great read that I highly recommend!

Head Cases has gotten quite a bit of buzz since it came out in January. It was a great start to a new crime fiction series.

The main character, Gardner Camden, is neurodivergent. He recognizes that he doesn't interact with people like most others do but in the course of the investigation, he makes the effort. A member of the special PAR unit he doesn't usually have to interact with anyone but his team. However, the case that has come across his desk is one he worked on before he was moved to the PAR unit. He was the lead investigator then so he is automatically the lead investigator again.

This is a mix of police procedural and psychological suspense. The PAR team kind of reminded me of the television show Criminal Minds. Every agent in PAR was sent to that unit for a reason - none of them chose it. But they are good at what they do.

I'm definitely looking forward to the next book in this series.

My review will be published at Girl Who Reads on Tuesday - https://www.girl-who-reads.com/2025/03/head-cases-by-john-mcmahon-review.html

Once you break the seal of "Head Cases", you will not stop reading until the case is closed. The question is, who will be left to close it? Within the Patterns and Recognition (PAR) unit, FBI Agent Gardner Camden leads a diverse troupe of investigators, as brilliant as they are quirky. PAR is both a secret weapon and a last resort for tackling unsolvable cases.
DNA at a murder scene determined to be from a known serial killer thought to be dead for years quickly lands the case on Camden's desk. More victims are piling up and the killer is leaving taunting clues daring the team to catch him if they can, Camden and team are literally reaching to get ahead of the killer, but there is trouble within. You see, you don't land in PAR because you are among the best and brightest. You are sent there when you have royally screwed up, but the FBI is not quite prepared to cut ties. Trust within the team hinders the investigation. A trust that puts their lives and the life of Camden's young daughter at stake, He cannot get this wrong.
Characters are well developed, human, flawed. McMahon skillfully weaves layers of intrigue beyond the case itself, adding depth without ever making it feel distracting or unnecessary. This is the first in a series that I cannot wait to continue reading!

My thanks to NetGalley and St. Martin’s Press – Minotaur Books for the ARC of this novel in exchange for my honest opinion.

Head Cases by John McMahon is a gripping, fast-paced crime thriller that pulls readers into a dark and gritty world of suspense. The novel follows a detective as he navigates a series of complex, twisted cases that challenge both his moral boundaries and his investigative skills. McMahon’s writing is sharp and immersive, with well-crafted characters and a tightly woven plot that keeps you on the edge of your seat.

The pacing is excellent, and the book does a great job of balancing action with moments of introspection, adding depth to the characters. While the twists are engaging, there are moments where the story can feel a bit predictable, but the overall intensity and compelling narrative make up for it.

Overall, Head Cases is an enjoyable read for fans of crime fiction, offering a solid 4-star experience with its dark themes, strong character development, and suspenseful storyline.

Good start to a series with some rough edges. Takes time to take off but a decent police procedural noentheless. Looking forward to the next some with the hope that the pacing gets a bit polished

Fans of Criminal Minds are going to love this one!

Let me lay the groundwork…
🔎 Misfit group of FBI agents
🔎 Fast paced setting
🔎 Killer who is hunting other killers

Agent Gardner Camden may be in charge of this case, but prepare yourself to adore the members of his team as well! Each of them has their own unique quirks that make them essential for solving this case.

There is an overarching sense of urgency that makes the pacing of the story fly by as our team chases their killer. The case, the motive, the killer, the people…all chef’s kiss!

This is the start of a series, but this book feels whole and complete by itself. I look forward to another installment with the PAR Unit and what intense case they might be working on next.

A great start to a new series. Started a little slow but then took off running! Highly entertaining for anyone who loves FBI profiler mysteries or True Crime.

This book was definitely one of my favorites so far this year. I love that the characters are all misfits in one way or another and have all epically messed up somewhere along the line, but all have their own unique skills that somehow manage to mesh together to carry a book that I couldn't put down. The plot was fast paced but nothing about it seemed rushed. The characters were fun and very multidimensional. I cannot wait for there to be more to this series and am very much looking forward to continuing it in the future!

This was a good debut! If you love police procedurals that follow a serial killer, then give this one a try. It is a bit slow paced at first, and while less dark than I expected, I enjoyed the storyline. I found Camden's character well fleshed out and his methods intriguing. I do wish we had a bit more background on the other members of the PAR unit (patterns and recognition) but maybe we will get more in the sequel!

Rating: 3.5/5

Thank you to St-Martin's Press, Minotaur books and NetGalley for the ARC. All opinions are my own.

This book gives TV show vibes—think Law & Order or Criminal Minds. The book centers around PAR (Patterns and Recognition), a unit of the FBI, composed of highly skilled individuals that are a bit quirkier than typical agents who are able to think outside the box. I’m glad to hear it’s a series because we get to know each member of the team during Headcase and I can’t wait for their characters to develop more.

In Headcase, Agent Gardner Camden responds to a call regarding a murder victim believed to be a serial killer. The way he died was unconventional and there are many unique clues that make PAR perfect for the case. As PAR begins their work on this murder, another serial killer comes up murdered and the patterns continue…the only problem is, it seems like the suspect might be inside the house (figuratively).

Camden has a job to get ahead of this new serial killer before those he cares about, or even himself, may fall into the killer’s hand as their next victim.

This book was engaging and Camden’s character was well fleshed out. I loved his unique thought process that the writing detailed perfectly. The story was gripping and I seriously was trying to put all the pieces together to figure out the killer myself (spoiler, I did not).

Thank you to Minotaur Books, St. Martin’s Press and NetGalley for the ARC.

Readers who love cat and mouse thrillers, serial killer profiling, and police procedural will want to pick up Head Cases by John McMahon. I found the writing captivating and increasingly claustrophobic as the showdown between a FBI agent in the Patterns and Recognitions Unit is attempting to identify and take down a killer. A mystery with cryptic clues, taunts, and increasing danger, this was a superior thriller!

Thanks to St. Martin's Press and NetGalley for the digital ARC of this book. First of all, I am happy that it is a series because I enjoyed this first book and look forward to others. I am admittedly a big fan of FBI/serial killer profiling and also puzzles/codes etc. so this was right in my wheelhouse. The characters were engaging and the story felt well paced. I also enjoy a well fleshed out villain which this book delivered.

3.75 Stars

Head Cases is the first book in a new series, and it certainly began with an interesting scenario. I found the intricacy of the case intriguing and as a result, was glued to the pages and was quite fascinated by the team's investigation. Because this is the first book in a new series, there is a certain amount of time taken to introduce the characters and develop their unique personalities, something I appreciated. But while the case was definitely interesting, it did fall back and make use of some tropes I was hoping would be avoided.

I really enjoyed the main character quite a bit. Gardner Camden is on the spectrum and I appreciated the author's research into this character's development; he was such a fascinating person to follow. Quite brilliant, but struggling with personal relationships, it was fascinating to see how his mind grasped concepts with which the rest of his team struggled, but completely missed nuances relating to social relationships. The rest of the characters complemented each other very well and I really enjoyed learning about their unique quirks and talents. While this book focused more on Camden's relationships, I am guessing future books will reveal more about the other characters and I can't wait as the glimpses we got were fascinating. All of them are there for something they did in the past and the author gave us just enough to tantalize.

The plot certainly began and ended with quite a bang, but the middle did slow down quite a bit. I didn't mind too much as I really enjoy investigations and love learning about the political machinations of organizations the author wants to include in their books. The themes of family, loyalty, secrets, and betrayal all found their place within the story line. I also didn't mind that the focus was more on Gardner Camden than on the others as I feel the author will expand on the characters in future books. However, I did wish the overall conclusion was a bit different than what it was as it was predictable and a bit tropey. I also didn't feel like the author took it as far 'into the dark side' as the subject merited. It felt like the author was afraid to go too dark and the brevity sometimes felt off as a result.

Head Cases was an intriguing first entry into a new series and I enjoyed the character development quite a bit. And while the plot was interesting and definitely had its high moments, especially the first thirty percent and the last twenty percent, overall I did find it somewhat predictable when the final outcome was revealed. I was really hoping it would have gone in a different direction. However, I did enjoy it and I will be looking out the second book when it is released.

I couldn't stop reading this! It was fantastic and intriguing!
I hope that this is going to be a long series!

I absolutely loved this read from start to finish! The plotting and pacing is absolutely on point, but what REALLY stood out to me is the character of Camden. There’s a Jason Bourne element here – a person who takes in too much analytical data at any given time without the ability to shut it off. Camden struggles to connect with people - and perhaps, at times – even his own feelings, but I appreciated how much I was able to feel for the character and the situations he was in despite a held-back character and writing style. It seemed like heightened drama was conveyed with very few words, and there was something about this tight, held-in nature that made those moments even more moving and impactful.

He is a perfectly imperfect hero, and I really felt like I was in his brilliant yet flawed head.
I kind of fell in love with Camden and his impetus to do the right thing no matter the cost, and I was so glad to learn that there’s another story with this character on the way!

This book – and hopefully series – is in the vein of the series Slow Horses (based on the Slough House series by Mick Herron), which is described as ‘an administrative purgatory for MI5 service rejects who have seriously failed a task but not badly enough to get sacked.’ Have I read or watched much of these? No – I’m not really into police procedurals, as I said, but my hubby has been RAVING about Slow Horses, so I’ll likely give it a full watch soon.

There’s something about rooting for the underdogs when they’re trying to save lives by bringing down bad actors while also trying to navigate within a bureau that is hostile to them. Talk about heightened stakes and DRAMA.

I highly recommend this read and can’t wait fo the next book!

Thank you St. Martin’s Press for the ARC!

"Head Cases" is a gripping, fast-paced police procedural that hooked me right from the start. As a huge fan of Criminal Minds, I was very excited to read this book about FBI agents in the Pattern and Recognition (PAR) unit, and it did not disappoint. It was such a page-turner, and I had so much fun reading this book. The mystery was compelling, and I was fully invested. I loved the well-developed, quirky characters, and the plot twists were surprising and well-executed. I was ecstatic to learn that this will be a series, and I can't wait for Book 2!

Thank you to NetGalley and Minotaur Books for the ARC in exchange for an honest review.

Overall this is a compelling story with really great characters and plot. The story has a good pace to it. Quite a few twists and turns I didn’t expect.

Thank you NetGalley for the copy

head cases by John McMahon published by St Martin press is a must read for all fans of Criminal Minds and profiling. The book follows a group of FBI agents as they hunt down a murderer.

Camden Gardner is great at solving problems and works at the FBI. He is an analytic genius with a love of puzzles.
Cassie Pardo is his police partner and they are part of the PAR unit. Par stands for Patters and Recognition unit.

The PAR unit is made up of a mathematician, a weapons expert, and a computer analyst. The FBI brings them in for cases no one else can seem to solve. The DNA on a murder victim comes back to a serial killer they thought died long ago.

The PAR unit usually works on cold cases but this is an active case and since none of them specialize in people, can they protect themselves and their loved ones before it's too late?

Huge thank you to John McMahon for partnering with NetGalley. I received an advanced reader copy of this book in exchange for my honest opinion and review.

This was a quick and easy read! A loved all the action and puzzles. I hope to read more from this author in the future!

Thank you NetGalley and Minotaur Books for this ARC in exchange for an honest review!