A deluge has flooded the high ground near Hanging Falls - but heavy rains aren't the only menace descending on Timber Creek. While on a scouting mission to pinpoint trail damage, officer Mattie Cobb and her K-9 partner, Robo, stumble upon a body floating at the edge of a lake. Robo catches human scent, which leads to an enigmatic forest-dweller who quickly becomes suspect number one. With help from veterinarian Cole Walker, Mattie identifies the victim and discovers an odd religious cult whose dress and manners harken back to the 19th century.

It’s October, hunting season in the Green Mountains - and the Vermont wilderness has never been more beautiful or more dangerous. Especially for nine-year-old Henry, who’s lost in the woods. Again. Only this time, he sees something terrible. When a young woman is found shot through the heart with a fatal arrow, Mercy thinks that something is murder. But Henry, a math genius whose autism often silences him when he should speak up most, is not talking.  

After their last deployment, when she got shot, her fiancé, Martinez, got killed, and his bomb-sniffing dog, Elvis, got depressed, soldier Mercy Carr and Elvis were both sent home, her late lover’s last words ringing in her ears: “Take care of my partner.” On the Fourth of July weekend, when all of Northshire celebrates with fun and frolic and fireworks, the dog alerts to explosives and they find a squalling baby abandoned near a shallow grave filled with what appear to be human bones. 

When Deputy Ken Brody's sweetheart goes missing in the mountains outside Timber Creek, Mattie Cobb and her K-9 partner Robo are called to search. But it's mid-October and a dark snow storm is brewing over the high country. And they're already too late. By the time they find her body, the storm has broken and the snow is coming down hard.

Deputy Mattie Cobb is in a dark place and has withdrawn from Cole Walker and his family to work on issues from her past. When she and her K-9 partner, Robo, get called to track a missing junior high student, they find the girl dead on Smoker's Hill behind the high school, and Mattie must head to the Walker home to break the bad news. But that's only the start of trouble in Timber Creek because soon another girl goes missing - and this time it's one of Cole's daughters.