Brian Robeson has a secret, he thinks of it as the Secret, he has been keeping it from his father and mother, and it is tearing him apart. His mother has asked his father for a divorce and his father now is living in Canada, while Brian lives in New York state with his mother. He knows she is having an affair, because he saw her in a car with the other man. His mother does not know he saw her and her boyfriend together. He has pulled away from her, because he blames her for the divorce.

He is on a bush plane with a pilot, named Jake or Jim, who shows him a bit about how to fly the plane. These skills become vital to Brian's survival after the pilot dies from a heart attack, while the plane is still in the air. Brian manages to point the plane towards a shore near a lake, in the hope of landing the plane safely. Instead the plane lands in the lake; Brian frees himself from the plane and swims to the shore. He is left with a probable concussion and a body which feels like it was run over by a truck, but he is alive.

Before he boarded the plane, his mother gave him a hatchet as a present. She thought he could use it while visiting his father in the forests of Canada. This present becomes invaluable to Brian's survival.

Brian wakes up the day after the crash thirstier than he has ever been before in his life. He decides to drink the lake water, which he does to the point of making himself sick. He realizes he needs to build a shelter, but as he is searching for wood to build the shelter he finds a rock area, that has a ledge for a roof and is hollowed out enough for him to sleep and live in.

His next need to fulfill is food, so he sets out to find some berries to eat. He finds some bushes teaming with berries and they help ease his hunger, but he eats too many of the berries and becomes violently ill from them. He calls the berries gut berries, because of the effect they have on his stomach. He searches for a better source of food and finds some raspberries to eat. As he is eating the raspberries he encounters a bear, which causes him to panic. He runs away from the bear, but notices the bear is not following him and he returns to the raspberry bushes.

He uses the hatchet that night as a source of protection, by keeping it near him while he sleeps. Brian is still waiting for rescuers to come and take him home. In the middle of the night, Brian hears something in his shelter, but, because he doesn't have a fire he cannot see what is in the shelter. He throws his hatchet towards the sound and two things happen, he sees sparks fly from where the hatchet has hit the wall of the shelter and he is in pain from the porcupine quills that are thrown into his leg.

The discovery of the sparks leads Brian to learn how to make a fire. This solves several problems for him as it gives him heat, light, and protection from the mosquitos, which have been tormenting him. He also builds a signal fire pit on top of his shelter, in case a plane comes looking for him.

Brian finds some turtle eggs, which he manages to swallow their contents raw. He decides to build a bow and make arrows to catch fish. As he is looking for wood for the bow, he hears an airplane overhead and he rushes to light his signal fire. Unfortunately, the plane does not see the fire and flies away, leaving Brian feeling alone and depressed.

After spending a night contemplating suicide, Brian decides he is a new person, who is a survivor. He manages to make a bow and arrow, which allows him to catch some fish, then he learns to hunt birds and rabbits.

By this time, he has been in the wilderness for forty-seven days, he doesn't look forward to being rescued anymore. He feels this is where he is going to live forever.

One day while he is hunting birds, he is attacked by a moose. The moose hits him again and again doing damage to his ribs. That same night a tornado rips through and destroys his shelter, leaving only the rock formation intact. The tornado does, however, raise up the tail of the plane from below the surface of the lake water.

This gives him an idea; he remembers the pilot telling him there is a survival pack stowed in the rear of the plane. Brian thinks if he can get this pack it would help in his survival.

First he builds a raft and uses it to get to the plane. He uses his hatchet to hack away the outer skin and gain entry to the plane. He retrieves the survival pack and finds among other items a radio transmitter.

He accidently leaves the transmitter on which leads a bush pilot to him. Brian at the time of his rescue has been alone in the wilderness for fifty-four days. He returns to his parents both physically and emotionally changed. He is slimmer than before and he looks at the world in a way he never did before, he is more observant and careful of his words.

He never reveals the Secret to his father. He also never tells his mother he knows her Secret, instead he just goes living life as a changed young man.

Brian goes from being an angry young man to a person who tries to understand the world around him. He never takes food or those he loves for granted again. The experience of being left to fend for himself changed him forever.