Right after he moves with his family to an old farmstead in the country, Billy Griffin, Jr. begins to experience a series of inexplicable events, beginning with the nighttime appearance of a woman at his bedroom window. Never one to believe in ghosts, he seeks alternative explanations for the lurking shadows, disappearing objects, and wafting scents. The strangest mystery of all is that his sister Beth, bitten by a rattlesnake and unable to go for help, is rescued by an ambulance that no one has called. Billy is not afraid of whatever is causing the events until one night he is chased by two huge, silent dogs which only turn away from him in answer to a shrill whistle he has never heard before. Soon after, he discovers the dogs' owner in an isolated cabin far from everyone else; it is Hebronetta Sikes, an old conjure woman who convinces Billy that he is dealing with a "real live ghost". He learns from his neighbor Mrs. Isbell that a girl named Catie Waldrop had once lived in the farmhouse where Billy now lives, and that she died soon after moving to California. Billy's fear turns first to fascination, then friendship and then, amazingly, to love. The relationship between flesh-and-blood Billy and ephemeral Catie is both humorous and poignant, and changes Billy's life forever.