It's winter in Rockton, a little town hidden deep in the wilds of the Yukon. Fresh off solving a series of grisly murders, Casey and Deputy Will Anders get stranded in a blizzard while they're tracking a runner from the town. Seeking shelter in a cave, they stumble across a woman who's been imprisoned in a deep well. Nicole Chavez - whom everybody thought had run away from town and died in the woods more than a year earlier - is alive. Barely. But she can't identify her captor: she's never seen his face. Was she taken by one of the hostiles who inhabit the wilderness around the town?