Fifteen years ago, Alex and Sandra Kelley were one person, until their father's quantum physicist friend opened up another dimension and let in a varcolac, a ruthless quantum intelligence bent on the destruction of everything in existence. As a side effect of the quantum duality, Alessandra became two separate people. Though they share the same memories and experiences from before the split, now each is a very different person.
These days, Alex works for a brilliant yet paranoid physicist named Ryan Oronzi, while Sandra is an officer with the Philadelphia Police Department. Sandra responds to a remarkable quantum event that exploded a local sports stadium, only to find her father's body among the dead. She doesn't even have time to mourn when she receives a call from him, apparently alive and well, from his home nearby. Soon, Sandra figures out that someone--perhaps her sister and the company she works for--has unleashed the varcolac upon the world again through a military-sponsored physics experiment.
With a confident, deft touch, engineer and author David Walton explores concepts of quantum physics while expertly weaving the narrative perspectives of two young women who seem to be the primary targets of varcolac attacks on space-time. The novel's mystery builds to a thrilling conclusion as physicists and police come together to try to defeat this utterly terrifying enemy, who uses time and space to attack Alex, Sandra and their family. --Rob LeFebvre, freelance writer and editor