After a viral rescue turns paramedic Mark Greenley into an overnight hero, Summit Strategies opens its doors to him—and reveals an empire where self-improvement is cover for control.

When paramedic Mark Greenley receives an anonymous scholarship, his investigation into its source leads to a Miami conglomerate called Summit Strategies. And to its charismatic cofounder Max Lightman, Mark’s father, a shadowy figure throughout his life. Mark also discovers a half brother named Kevin, a fixture at Summit who died under suspicious circumstances. These are the least of the revelations.

The corporation specializes in psychological training sessions built on a highly protected program called “the tech.” Strangest of all is the heart of the empire: the Vault, a massive underground facility holding the deepest and darkest secrets of millions of people worldwide. The more Mark learns, the more he fears he hasn’t been invited to join the Summit family. He’s been lured.

Whatever happened to Kevin—and why—Mark is determined to find out as he navigates a treacherous world of deadly corporate intrigue, insidious manipulation, psychological warfare, and a search for the truth that could destroy him.

© 2026 by Andrew Mayne, all rights reserved.

<p>Andrew Mayne is the Amazon Charts and <i>Wall Street Journal</i> bestselling author of <i>The Girl Beneath the Sea</i>, <i>Black Coral</i>, <i>Sea Storm</i>, <i>Sea Castle</i>, and <i>Dark Dive</i> in his Underwater Investigation Unit series; <i>The Final Equinox</i> and <i>Mastermind</i> in the Theo Cray and Jessica Blackwood series; <i>The Naturalist</i>, <i>Looking Glass</i>, <i>Murder Theory</i>, and <i>Dark Pattern</i> in the Theo Cray series; <i>Angel Killer</i>, <i>Name of the Devil</i>, and the Edgar Award–nominated <i>Black Fall</i> in his Jessica Blackwood series; and <i>Mr. Whisper</i>, <i>Impostor Syndrome</i>, and <i>Chaos Man</i> in the Specialists series. He was the star of A&amp;E’s <i>Don’t Trust Andrew Mayne</i> and swam with great white sharks using an underwater stealth suit he designed for the Shark Week special <i>Andrew Mayne: Ghost Diver</i>. He worked on creative applications for artificial intelligence and served as the science communicator for OpenAI, the creators of ChatGPT, and is the cofounder of Interdimensional.ai. For more information, visit www.andrewmayne.com.</p>