John McMahon
Critically-acclaimed author of the P.T. Marsh Series
​
• Finalist for EDGAR AWARD (Best First Novel)
• Finalist for THRILLER AWARD (Best First Novel)
• NY Times Top 10 Crime Novels of Year
(for THE GOOD DETECTIVE & THE EVIL MEN DO)
• Amazon Editor's Pick (Best Mystery): A GOOD KILL
​
Author of HEAD CASES​
• USA TODAY Best Seller
• In Development as a TV series on HBO Max
Out 1/13/26
Inside Man
(sequel to Head Cases)
​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.?
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Matthew Quirk, New York Times best-selling author
Praise for "HEAD CASES"
"A masterfully-done game of cat
and mouse with an unforgettable
cast of characters."
"Grabbed me from page one!"
J.A. Jance,
"Gripping, twisty, and atmospheric."
Karen Dionne,
Best-selling author of
The Marsh King's Daughter
News & Appearances
* INSIDE MAN BOOK TOUR *
APPEARANCES:
Jan 12th, 2026
PHOENIX, AZ
Poisoned Pen Books, 7:00 pm
Jan 13th, 2026
SANTA MONICA, CA
DIESEL, A Bookstore, 6:30 pm
Jan 14th, 2026
HOUSTON, TX
Murder By the Book, 6:30 pm
Jan 17th, 2026 (Saturday)
ORANGE, CA
Book Carnival, 2:00 pm
Jan 20th, 2026
ST. LOUIS
St. Louis County Library, TBD Evening Discussion
