The central character is 12 year old Dick Milton who has come with his mother and young brothers and sisters to Jefferson, a small New England town, while Mr. Milton is in South America. Dick's grandfather, Roger Devons, had been a much beloved and respected man in the community. But a feeling of antipathy among the neighbors, is evident from the start.
At a loss to explain it, Dick talks to a new friend, Jerry Stewart, who has just returned to Jefferson from Navy duty and who promises to help. The mystery is ordinary, involving Jerry and the dead Roger Devons in unexpected ways. But the solving also reveals the social temper of a town, its families and a boy growing up.