In 1880, a boy is captured and held in a tack shed. Two men stand nearby discussing what to do with him after the boy witnessed one of the men burying something secret. The boy, who doesn’t look like anyone else in the area, knows he has to escape but can’t risk exposing himself as defenseless. Suddenly, he gets an idea. He opens the window, rubs mud from his boot on the windowsill, and sits back down to wait.

Thirteen-year-old Jake Evans is awakened at four in the morning by his dad as they prepare to begin their two-month trip to 10 national parks across the Western United States. Jake is grumbly at first, but looking at a photo of him and his grandpa after planting the final tree of an orchard together helps boost his spirits. Jake comes downstairs for breakfast and wakes up quickly when his grandma gives him a note that his grandpa left for him. Jake’s grandpa died six months before, and Jake misses him dearly. Jake recently fell out with his friends at school, and his older brother Nick has moved away for college. Finding this note is like being connected to his grandpa again, and Jake figures out that it is actually a clue to something.