Eleven-year-old Cooper Cameron likes things to be in order. When he eats, he chews every bite three times on each side. Sometimes he washes his hands in the air with invisible water. He invented these rituals after the death of his beloved grandfather to protect others he loves from terrible harm.

But when Cooper's strange behavior drives a wedge between his parents, and his relationship with his older sister, Caddie, begins to fray, his mother's only solution is to take Cooper and Caddie to the family cabin for the summer.

Armed with a collection of rocks, his pet frog, and his notebook, Cooper vows to cure himself and bring his damaged family back together.