The Navigator (Broché)

Owen turned to Cati, but she was staring into the woods, her face a mask of fear. Far off, but moving closer, were two figures ; both white, both faceless, seeming to glide between the trees. "The Harsh," whispered Cati. "They're here." Owen's ordinary life is turned upside-down the day he gets involved with the Resisters and their centuries-long feud with an ancient, evil race. The Harsh, with their icy blasts and relentless onslaught, have a single aim - to turn back time and eliminate all life.
Unless they are stopped, everything Owen knows will vanish as if it has never been. But time is running out...