A blackout, a derailment, a flood—when disasters align with a mysterious countdown, Theo Cray, Jessica Blackwood, Brad Trasker, and Sloan McPherson hunt the engineer who scripts chaos.

A train derails in Idaho, nearly causing a nuclear disaster. An inferno at a battery facility in Florida disrupts the electrical grid for days. A potentially devastating failure is discovered at Virginia’s Mud River Dam. To computational biologist Theo Cray, these aren’t mere infrastructure accidents. They are virtually undetectable acts of sabotage.

Theo sees a mathematical pattern to the madness that few others can comprehend—except for his associates: rogue FBI agent Jessica Blackwood, private security specialist Brad Trasker, and Florida underwater investigator Sloan McPherson. If Theo’s intuition and calculations are correct, the disasters are just a warm-up. The worst is yet to come—a catastrophe that could trigger the deaths of millions across the country.

Now Theo and his team are on the hunt for a mysterious saboteur whose only motive is to spread panic and chaos. And with every tick of the clock, his unthinkable endgame is getting closer to becoming a terrifying reality.

Andrew Mayne is the Amazon Charts and Wall Street Journal bestselling author of The Girl Beneath the Sea, Black Coral, Sea Storm, Sea Castle, and Dark Dive in his Underwater Investigation Unit series; The Final Equinox and Mastermind in the Theo Cray and Jessica Blackwood series; The Naturalist, Looking Glass, Murder Theory, and Dark Pattern in the Theo Cray series; Angel Killer, Name of the Devil, and the Edgar Award–nominated Black Fall in his Jessica Blackwood series; and Impostor Syndrome and Mr. Whisper in the Specialists series. He was the star of A&E’s Don’t Trust Andrew Mayne and swam with great white sharks using an underwater stealth suit he designed for the Shark Week special Andrew Mayne: Ghost Diver. 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.