Ten year old Ralph lives with his mother and step-father on the family farm in north central Kansas. It's a warm Indian summer day, fall of 1937. Ralph and his buddies, Rusty and Teag, take a Saturday venture to the twin hills west of town to search for arrowheads and discover a rattlesnake infested cave. Their cave exploration yields Indian relics as well as a young woman's skeleton. Teag sits on a rattlesnake and is bitten. After church the next day, Ralph and his mother visit Aunt Minnie at the Old Folks Home. Ralph has befriended another pensioner of the Home, Old Eagle, a half-breed Crow Indian scout and Civil War veteran, who becomes a ready source for much Pawnee lore. Tuesday an archeology professor from the University and his graduate student arrive to investigate the find. (Ralph's sister is in nursing college and the graduate student is her beau.) Ralph is excused from school to help at their research camp. Someone (or an Indian Spirit?) repeatedly sabotages their investigation, camouflaging the cave's true entrance, then a suspicious prairie fire destroys much of the professor's equipment. Eventually the cave entrance is located and entered. The important relics are no longer there. The professor departs. The story is not over. Old Eagle insists that the Spirits have more in store for Ralph and encourages Ralph to revisit the site, and to take his classmate cousin Ann...