An Erin Calloway Thriller A cryptic message. A missing person. A secret someone will kill to protect. When Detective Erin Calloway gets a text from someone she hasn't heard from in years, she assumes it's a mistake. Then the sender vanishes. What starts as a routine missing-person case pulls Erin into a conspiracy of defense contractors, foreign operatives, and a revolutionary AI system with the power to reshape modern warfare. The deeper she digs, the clearer it becomes: some secrets aren't hidden. They're protected. And whoever's protecting this one will do whatever it takes to keep her from finding the truth. Shadow System is the second Erin Calloway Thriller. A gripping suspense novel filled with mystery, danger, and shocking twists that will keep readers guessing until the final page. Perfect for readers of Robert Dugoni, David Baldacci, and Daniel Silva, as well as fans of conspiracy thrillers, international mysteries, and fast-paced suspense. New to the series? Start with The Silent Beneath.