Everywhere, electrical power suddenly ceases, the Sun dims, cities come to a halt, and inhabitants vanish. A terrifying chaos grips the world. But a small, clandestine group of warriors has been preparing for this moment for centuries. Everyone's hopes rest on two strangers, a thousand miles apart, who hold the keys to the world's survival: Dylan Barnes and Lucy Devereau. He, a martial arts instructor teaching the art of inner balance, but plagued by shadows only he can see and voices only he can hear. She, a private investigator earning a living by trolling the lives of others, but haunted by birth-right–and the mystery of her true parents. Now, as the world around them fades to black—perhaps forever—Lucy and Dylan find themselves on the front lines of a deadly battle against something ancient, horrifying; impossibly dark.