Head Cases

John McMahon has a winner with Head Cases, the first book in the PAR Unit series. Filled with unusual characters hunting down a murderer seeking his own brand of justice, the FBI’s Patterns and Recognition (PAR) unit is generally tasked with solving cold cases. The team consists of five misfit agents led by Frank Roberts, but the main character is Special Agent Gardner Camden.

A serial killer from one of Gardner’s solved cases, thought to be dead for more than a decade, is found murdered. Soon, there’s another similar case. The killer has left clues and riddles, but can the team solve them?

Gardner is intelligent, confident, all business, and has an eidetic memory. He thinks in terms of layers and patterns, avoids friendships with most, and can come across as arrogant. He has an affinity for riddles, puzzles, and codes. I enjoyed how the author brought to life both the personal and professional lives of Gardner. As readers learn his background, it provides insight into his thoughts, behaviors, and actions. It was fascinating to see how Gardner’s mind worked to solve the various puzzles.

Frank is a career agent and the other members include a mathematician, a sniper and weapons expert, and a computer analytics specialist. The secondary and tertiary characters are reasonably well-drawn for the first book in the series and I would expect the repeat characters to gain more depth as the series progresses. It was also delightful to see how this team of supposed misfits worked so well together.

I was immediately intrigued by the storyline and the complexities in the plot. It kept me captivated throughout the novel. It was fascinating to see the story unfold. Full of suspense, this thriller looks at justice through the eyes of Gardner, but readers also get a feel for the antagonist and the vengeance that is sought.

 The conflicts move the story through some twists and turns as the story gradually builds momentum and finishes with some surprises and an action-packed finish. The novel also illuminated the politics that can go on behind the scene for agents that don’t fit the traditional mold.

Overall, this was a compelling and dynamic story with excellent characterization, good pacing, and a great plot that includes solid procedural details. I can’t wait to read the next book in the series which is expected in 2026. Those who enjoy crime thrillers and FBI investigations with extraordinary characters as well as those who enjoy solving puzzles will likely enjoy this novel.

St. Marin’s Press – Minotaur Books and John McMahon provided a complimentary digital ARC of this novel via NetGalley. All opinions expressed in this review are my own. The publication date is currently set for January 28, 2025.