Head Cases by John McMahon was a great read in early 2025, a crime thriller with puzzles to solve along the way. This made Inside Man, the sequel to Head Cases, a must-read. While it wasn’t the experiences of reading the first book, it was definitely an enjoyable ride filled with twists and turns.
FBI Agent Gardner Camden is an analytical genius with an affinity for puzzles. He and his squad of brilliant yet quirky agents make up the Patterns and Recognition (PAR) unit, the FBI’s hidden edge, brought in for cases that no one else can solve.
PAR’s latest case involves a militia group stockpiling weapons. When their confidential informant in the case is killed, it quickly becomes clear that the militia did not kill him.
As the squad looks into the evidence surrounding his murder, an unidentified man is caught on camera with their informant. This mystery man’s picture is connected to another case at the FBI, an unsolved series of murdered women, buried in the ground in north Florida. Could they have uncovered a serial killer? And if so, what is his connection to their C.I.?
As PAR juggles an investigation into both the dead women and the militia, they enroll a new informant, only to find the case escalating in dangerous ways. How will PAR handle a case that increasingly looks like a terrorist plot? And in the serial case, with no puzzles or witnesses, and few leads, how will a group set up to decode riddles be successful?
Mystery style crime thrillers are always an exciting read, but when puzzles and patterns are included such novels like Head Cases and Inside Man, it’s even more exciting. This latest novel in the Head Cases series didn’t give off the level of excitement as the first book, but it still was a fun ride.
Of course it’s FBI Agent Gardner Camden which makes this novel what it is. His character is quirky and unique, giving us a unique spin on the stereotypical FBI Agent. A bit more off the beaten path, but reminds me slightly of Spencer Reid from Criminal Minds. While all the characters in the PAR unit have a unique skill and personality, it’s Camden that really makes the story what it is.
I found the first novel a bit more smooth of a read, and this second story to be a little clunky. It had moments of, “this is not as good as the first” to quickly making me unable to put it down. Inside Man features a few mysteries to solve, but also has heart. You truly care what happens to each person in the PAR unit and those in their sphere. It’s emotional, while also thrilling and riveting.
Inside Man by John McMahon is an excellent followup and continuation of the Head Cases series. I am down for whatever may come next, but also satisfied if this is the end to these books. McMahon gave us another thrilling few cases to be solved by PAR and brought heart to go along with it.
Inside Man: A Head Cases Novel hits bookstores everywhere on January 13, 2026 from Minotaur Books. The audiobook, narrated by Will Damron, is available for preorder via Libro.fm!
