Detective Casey Duncan has noticed fewer and fewer residents coming in to the hidden town of Rockton, and no extensions being granted. Her boyfriend, Sheriff Eric Dalton, presumes it's the natural flux of things, but Casey's not so sure. It seems like something bigger is happening in the small town they call home. When an injured hiker stumbles from the woods, someone who seems to have come to the Yukon for a wilderness vacation but instead is now fighting for her life, it's all hands on deck. What -- or who -- attacked this woman, and why? With the woman unconscious, and no leads, Casey and Eric don't know where the threat is coming from. Plus, the residents of their deeply secretive town are uneasy with this stranger in their midst. Everyone in Rockton wants this mystery solved -- and fast.