Brian is a sixteen-year-old woodsman who feels out of place in modern society after surviving a plane crash at age fourteen. Preferring a simple life in nature over the noise of the civilized world, he arranges to homeschool himself in the wilderness. He possesses advanced survival skills, favoring traditional tools like a bow and arrow over modern firearms. When a severely injured dog arrives at his camp, Brian sets out to find the cause, tracking an aggressive predator toward the home of his friends.

The Dog is a dark-haired malamute, bred by Cree trappers for companionship and pulling sleds. She arrives at Brian's camp in the middle of the night with a massive, foot-and-a-half-long wound stretching down her torso. Exceptionally tough and calm, she requires thirty-two stitches but never acts aggressively toward Brian. She quickly forms a bond with him, using her acute senses to warn him of danger as they travel north together.

Kay-Gwa-Daush, also known as Susan, is the sixteen-year-old daughter of David and Anne Smallhorn. Her Cree name translates to "the attempter," reflecting a fearless nature that her parents encourage. Having been away at school during Brian's first visit to her family's camp, she spends her summers on an arrowhead-shaped island in the northern Canadian woods. Like Brian, she possesses a deep understanding of the natural world.

The Bear is a highly unusual, massive predator roaming the woods near the Smallhorns' island camp. It is easily identifiable by its tracks, which show a missing left claw and a broken right claw. Unlike typical wildlife that kills for food, this animal exhibits aggressive and taunting behavior, stalking humans and domesticated animals without provocation. Its presence disrupts the natural balance of the woods, prompting Brian to track it.

David is a Cree trapper who spends part of the year living with his family on a remote island camp. He previously hosted Brian for a few weeks after Brian's initial survival experience, establishing a lasting connection. He maintains a traditional lifestyle while utilizing some modern tools like rifles and short-wave radios to protect and connect his family in the harsh Canadian wilderness.

Anne is the wife of David Smallhorn and mother to Susan and two younger children. She lives on a remote arrowhead-shaped island during the summer months, managing a team of sled dogs and maintaining the family's homestead. She warmly welcomed Brian into her home two years prior, leaving him with fond memories of her family's hospitality.