Jake and Taylor Wilder have been taking care of themselves for a long time. Their father abandoned the family years ago, and their mother is too busy working and running interference between the boys and her boyfriend, Bull, to spend a lot of time with them. Thirteen-year-old Jake spends most of his time reading. He pores over his father's journal, which is full of wilderness facts and survival tips. Eleven-year-old Taylor likes to be outside playing with their dog, Cody, or joking around with the other kids in the neighborhood. But one night everything changes. The boys discover a dangerous secret that Bull is hiding. And the next day, they come home from school to find their mother unconscious in an ambulance. Knowing they are no longer safe and with nowhere else to go, the Wilder boys head off in search of their father. They only have his old letters and journal to help them, but they have to make it. It's a long journey from the suburbs of Pittsburgh to the wilderness of Wyoming; can the Wilder boys find their father before Bull catches up with them?