Six years after a drunk driver kills his mother and brother on Halloween night, Ellis Herrick awakens to find himself changed by a mysterious power. For the next two centuries Ellis pursues answers to the riddle of his immortality, a journey that takes him from the irredeemable past to the far reaches of outer space - and ultimately to the innermost caverns of his wounded psyche. Harbinger is a novel of adventure, evolution, imperishable love, and the shifting nature of personal reality.

"This crackling road trip through the apocalypse offers thrills all the way to its explosive, satisfying finale." -- Publishers Weekly "Relentless, terrifying, and affecting, this book left me feeling like I'd been strapped to the front of the car like Mad Max in Fury Road--not realizing that it was taking me to an emotional ending that would leave me gutted. I've been a huge fan of Skillingstead's work for years, but in The Chaos Function he's outdone himself!" -- Daryl Gregory, award-winning author of Spoonbenders For readers of the best-selling novels Sleeping Giants and Dark Matter, an intense, high-stakes thriller with a science-fiction twist that asks: If technology enabled you to save the life of someone you love, would you do so even if it might doom millions? Olivia Nikitas, a hardened journalist whose specialty is war zones, has been reporting from the front lines of the civil war in Aleppo, Syria. When Brian, an aid worker she reluctantly fell in love with, dies while following her into danger, she'll do anything to bring him back. In a makeshift death chamber beneath an ancient, sacred site, a strange technology is revealed to Olivia: the power to remake the future by changing the past. Following her heart and not her head, Olivia brings Brian back, accidentally shifting the world to the brink of nuclear and biological disaster. Now she must stay steps ahead of the guardians of this technology, who will kill her to reclaim it, in order to save not just herself and her love, but the whole world.