Philip and Ruth, 10 and 8, are staying with their rather strict Aunt Margaret in the south of England while their parents are overseas during the late 1940's. While building a secret hideout in the woods, the children meet Terry, a gypsy boy who shares the secrets of the forest with them. Later, when Terry falls from a tree and suffers a long illness, Philip and Ruth do all they can to help him. Eventually he dies, and when Ruth asks many challenging questions about death, she hears a beautiful parable about a chestnut planted in the earth.