Echo

ISOLATED. MURDERED. GHOSTS IN THE MACHINE.

Book Five of the Quake Runner: Alex Kayne Thrillers

ALEX Kayne has spent years running from the law.

Now she's running toward a killer.

When a young freelancer's body is discovered hundreds of miles from home, the case looks like another tragedy destined to go cold. But Alex sees the pattern no one else can. Remote workers. Isolated lives. Digital identities that keep moving, keep speaking, keep earning—long after the real person is dead.

Someone is murdering the invisible and leaving echoes behind.

With QuIEK, her quantum-based AI, Kayne can slip through any system, unlock any secret, and vanish from nearly any trap. But this time, the enemy runs in the same virtual terrain. The killer lives in the shadows between real life and online existence, turning lonely people into puppets, trophies, and ghosts in the machine.

To stop them, Kayne must return to the life she thought she'd left behind: disguises, dead drops, stolen cars, false identities, and the constant pulse-pounding pressure of being hunted from every direction.

And somewhere in Seattle, the next victim is already being erased.

ECHO is a high-velocity techno-thriller about identity, obsession, justice, and the terrifying question of what remains of us when the world only knows our digital shadow. Fast, moody, razor-edged, and relentless, this is Alex Kayne at her most dangerous—and her most vulnerable.

"J. Kevin Tumlinson's thrillers are a throat-clutching ride. If you love historical mysteries crafted with action and adventure, don't miss [Tumlinson's books]!"
— James Rollins, #1 New York Times Bestseller of Arkangel

"With the pacing of a blockbuster and the depth of literary fiction, Kevin Tumlinson crafts stories that are both intellectually engaging and impossible to put down—prepare to lose sleep."
— J.D. Barker, New York Times Bestselling Author

"Where [Tumlinson's work] excels most is its cross-genre appeal. All of these disparate elements shouldn't work together, but they do, and a big reason is that this novel is just so damn fun."
— Jeff Daugherty, BookTrib